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Glaubrecht M, Zorn C. More slug(gish) science: Another annotated catalogue on types of tropical pulmonate slugs (Mollusca, Gastropoda) in the collection of the Natural History Museum Berlin. ZOOSYST EVOL 2012. [DOI: 10.1002/zoos.201200005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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202
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Hautier L, Stansfield FJ, Allen WRT, Asher RJ. Skeletal development in the African elephant and ossification timing in placental mammals. Proc Biol Sci 2012; 279:2188-95. [PMID: 22298853 DOI: 10.1098/rspb.2011.2481] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
We provide here unique data on elephant skeletal ontogeny. We focus on the sequence of cranial and post-cranial ossification events during growth in the African elephant (Loxodonta africana). Previous analyses on ossification sequences in mammals have focused on monotremes, marsupials, boreoeutherian and xenarthran placentals. Here, we add data on ossification sequences in an afrotherian. We use two different methods to quantify sequence heterochrony: the sequence method and event-paring/Parsimov. Compared with other placentals, elephants show late ossifications of the basicranium, manual and pedal phalanges, and early ossifications of the ischium and metacarpals. Moreover, ossification in elephants starts very early and progresses rapidly. Specifically, the elephant exhibits the same percentage of bones showing an ossification centre at the end of the first third of its gestation period as the mouse and hamster have close to birth. Elephants show a number of features of their ossification patterns that differ from those of other placental mammals. The pattern of the initiation of the ossification evident in the African elephant underscores a possible correlation between the timing of ossification onset and gestation time throughout mammals.
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Affiliation(s)
- Lionel Hautier
- Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ, UK.
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204
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Frazzetta TH. Flatfishes, Turtles, and Bolyerine Snakes: Evolution by Small Steps or Large, or Both? Evol Biol 2011. [DOI: 10.1007/s11692-011-9142-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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205
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Wägele H, Klussmann-Kolb A, Kuhlmann M, Haszprunar G, Lindberg D, Koch A, Wägele JW. The taxonomist - an endangered race. A practical proposal for its survival. Front Zool 2011; 8:25. [PMID: 22029904 PMCID: PMC3210083 DOI: 10.1186/1742-9994-8-25] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2011] [Accepted: 10/26/2011] [Indexed: 12/02/2022] Open
Abstract
BACKGROUND Taxonomy or biological systematics is the basic scientific discipline of biology, postulating hypotheses of identity and relationships, on which all other natural sciences dealing with organisms relies. However, the scientific contributions of taxonomists have been largely neglected when using species names in scientific publications by not citing the authority on which they are based. DISCUSSION Consequences of this neglect is reduced recognition of the importance of taxonomy, which in turn results in diminished funding, lower interest from journals in publishing taxonomic research, and a reduced number of young scientists entering the field. This has lead to the so-called taxonomic impediment at a time when biodiversity studies are of critical importance.Here we emphasize a practical and obvious solution to this dilemma. We propose that whenever a species name is used, the author(s) of the species hypothesis be included and the original literature source cited, including taxonomic revisions and identification literature - nothing more than what is done for every other hypothesis or assumption included in a scientific publication. In addition, we postulate that journals primarily publishing taxonomic studies should be indexed in ISISM. SUMMARY The proposal outlined above would make visible the true contribution of taxonomists within the scientific community, and would provide a more accurate assessment for funding agencies impact and importance of taxonomy, and help in the recruitment of young scientists into the field, thus helping to alleviate the taxonomic impediment. In addition, it would also make much of the biological literature more robust by reducing or alleviating taxonomic uncertainty.
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Affiliation(s)
- Heike Wägele
- Zoologisches Forschungsmuseum Alexander Koenig, Adenauerallee 160, 53113 Bonn, Germany
| | - Annette Klussmann-Kolb
- Institute for Ecology, Evolution and Diversity, Goethe-University, Siesmayerstrasse 70, 60054 Frankfurt am Main, Germany
| | - Michael Kuhlmann
- Department of Entomology, The Natural History Museum, Cromwell Road, London SW7 5BD, UK
| | - Gerhard Haszprunar
- Zoologische Staatssammlung München, Münchhausenstraße 21, 81247 München, Germany
| | - David Lindberg
- Department of Integrative Biology and Museum of Paleontology, University of California, Berkeley, CA 94720-4780, USA
| | - André Koch
- Zoologisches Forschungsmuseum Alexander Koenig, Adenauerallee 160, 53113 Bonn, Germany
| | - J Wolfgang Wägele
- Zoologisches Forschungsmuseum Alexander Koenig, Adenauerallee 160, 53113 Bonn, Germany
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Hu J, Jiang Z, Zhang C, Xiao F, Hu H. Bird diversity and the conservation value of a new Ramsar site: Guangdong Haifeng Wetlands, China. Integr Zool 2011; 6:266-78. [PMID: 21910846 DOI: 10.1111/j.1749-4877.2011.00252.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Wetlands are critical habitats for birds. However, wetlands are being degraded at an accelerating rate due to global human activity, and a disproportionate fraction of wetland-dependent bird species are in decline. We evaluated the conservation value of a new Ramsar site, Guangdong Haifeng Wetlands, China, for birds, by comparing bird communities (using line transect data) in 3 different districts: Gongping, Dongguan Lian'anwei and Dahu. We recorded 139 species of birds, including 26 species that are protected at a national level. Dahu had the highest species richness and diversity, whereas Dongguan Lian'anwei had the highest abundance of birds and the lowest species diversity. Finally, Gongping had both the lowest species richness and the lowest abundance. The endemism of constituent species differed among districts, and the bird communities were complementary. There were significant seasonal differences in the species richness and the number of individuals. Spring had the highest species richness and diversity. The present study identifies the high conservation value of Haifeng Wetlands for both waterbirds and terrestrial birds. Our findings suggest that conservation efforts in Haifeng Wetlands and other wetlands should focus not only on wintering migratory birds, but also on resident birds. To accomplish effective conservation, we should consider the reserve and surrounding wetlands as a whole, incorporating ecological research, education and local economic development.
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Affiliation(s)
- Junhua Hu
- Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, China
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Abstract
To understand how extant viruses interact with their hosts, we need a historical framework of their evolutionary association. Akin to retrovirus or hepadnavirus viral fossils present in eukaryotic genomes, bracoviruses are integrated in braconid wasp genomes and are transmitted by Mendelian inheritance. However, unlike viral genomic fossils, they have retained functional machineries homologous to those of large dsDNA viruses pathogenic to arthropods. Using a phylogenomic approach, we resolved the relationships between bracoviruses and their closest free relatives: baculoviruses and nudiviruses. The phylogeny showed that bracoviruses are nested within the nudivirus clade. Bracoviruses establish a bridge between the virus and animal worlds. Their inclusion in a virus phylogeny allowed us to relate free viruses to fossils. The ages of the wasps were used to calibrate the virus phylogeny. Bayesian analyses revealed that insect dsDNA viruses first evolved at ∼310 Mya in the Paleozoic Era during the Carboniferous Period with the first insects. Furthermore the virus diversification time frame during the Mesozoic Era appears linked to the diversification of insect orders; baculoviruses that infect larvae evolved at the same period as holometabolous insects. These results imply ancient coevolution by resource tracking between several insect dsDNA virus families and their hosts, dating back to 310 Mya.
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208
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Evans HC, Elliot SL, Hughes DP. Ophiocordyceps unilateralis: A keystone species for unraveling ecosystem functioning and biodiversity of fungi in tropical forests? Commun Integr Biol 2011; 4:598-602. [PMID: 22046474 DOI: 10.4161/cib.4.5.16721] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2011] [Accepted: 05/31/2011] [Indexed: 11/19/2022] Open
Abstract
Ophiocordyceps unilateralis (Ascomycota: Hypocreales) is a specialized parasite that infects, manipulates and kills formicine ants, predominantly in tropical forest ecosystems. We have reported previously, based on a preliminary study in remnant Atlantic Forest in Minas Gerais (Brazil), that O. unilateralis represents a species complex. On each of the four species of infected carpenter ant (Camponotus) collected, the fungus-characterized macroscopically by a single stalk arising from the dorsal neck region on which the sexual structures (stromatal plates) are borne laterally-can readily be distinguished both microscopically and functionally. Here, we describe and discuss the biology, life cycle and infection strategies of O. unilateralis s.l. and hypothesize that there may be hundreds of species within the complex parasitizing formicine ants worldwide. We then address the diversity within related hypocrealean fungi, with particular reference to symbionts (mutualists through to parasites), and argue that the widely-quoted total of extant fungi (1.5 million species) may be grossly underestimated.
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Affiliation(s)
- Harry C Evans
- Department of Entomology; Universidade Federal de Viçosa (UFV); Viçosa; Minas Gerais, Brazil
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209
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YOUNG MARKT, BELL MARKA, DE ANDRADE MARCOB, BRUSATTE STEPHENL. Body size estimation and evolution in metriorhynchid crocodylomorphs: implications for species diversification and niche partitioning. Zool J Linn Soc 2011. [DOI: 10.1111/j.1096-3642.2011.00734.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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210
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211
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Studying sensorimotor integration in insects. Curr Opin Neurobiol 2011; 21:527-34. [DOI: 10.1016/j.conb.2011.05.030] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2011] [Revised: 05/22/2011] [Accepted: 05/27/2011] [Indexed: 01/20/2023]
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212
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Mora C, Tittensor DP, Adl S, Simpson AGB, Worm B. How many species are there on Earth and in the ocean? PLoS Biol 2011; 9:e1001127. [PMID: 21886479 PMCID: PMC3160336 DOI: 10.1371/journal.pbio.1001127] [Citation(s) in RCA: 970] [Impact Index Per Article: 74.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2010] [Accepted: 07/13/2011] [Indexed: 11/23/2022] Open
Abstract
The diversity of life is one of the most striking aspects of our planet; hence knowing how many species inhabit Earth is among the most fundamental questions in science. Yet the answer to this question remains enigmatic, as efforts to sample the world's biodiversity to date have been limited and thus have precluded direct quantification of global species richness, and because indirect estimates rely on assumptions that have proven highly controversial. Here we show that the higher taxonomic classification of species (i.e., the assignment of species to phylum, class, order, family, and genus) follows a consistent and predictable pattern from which the total number of species in a taxonomic group can be estimated. This approach was validated against well-known taxa, and when applied to all domains of life, it predicts ~8.7 million (± 1.3 million SE) eukaryotic species globally, of which ~2.2 million (± 0.18 million SE) are marine. In spite of 250 years of taxonomic classification and over 1.2 million species already catalogued in a central database, our results suggest that some 86% of existing species on Earth and 91% of species in the ocean still await description. Renewed interest in further exploration and taxonomy is required if this significant gap in our knowledge of life on Earth is to be closed.
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Affiliation(s)
- Camilo Mora
- Department of Biology, Dalhousie University, Halifax, Nova Scotia, Canada.
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Abstract
For most organisms, the number of described species considerably underestimates how many exist. This is itself a problem and causes secondary complications given present high rates of species extinction. Known numbers of flowering plants form the basis of biodiversity "hotspots"--places where high levels of endemism and habitat loss coincide to produce high extinction rates. How different would conservation priorities be if the catalog were complete? Approximately 15% more species of flowering plant are likely still undiscovered. They are almost certainly rare, and depending on where they live, suffer high risks of extinction from habitat loss and global climate disruption. By using a model that incorporates taxonomic effort over time, regions predicted to contain large numbers of undiscovered species are already conservation priorities. Our results leave global conservation priorities more or less intact, but suggest considerably higher levels of species imperilment than previously acknowledged.
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214
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Powers TO, Neher DA, Mullin P, Esquivel A, Giblin-Davis RM, Kanzaki N, Stock SP, Mora MM, Uribe-Lorio L. Tropical nematode diversity: vertical stratification of nematode communities in a Costa Rican humid lowland rainforest. Mol Ecol 2011; 18:985-96. [PMID: 19207247 DOI: 10.1111/j.1365-294x.2008.04075.x] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Comparisons of nematode communities among ecosystems have indicated that, unlike many organisms, nematode communities have less diversity in the tropics than in temperate ecosystems. There are, however, few studies of tropical nematode diversity on which to base conclusions of global patterns of diversity. This study reports an attempt to estimate nematode diversity in the lowland tropical rainforest of La Selva Biological Research Station in Costa Rica. We suggest one reason that previous estimates of tropical nematode diversity were low is because habitats above the mineral soil are seldom sampled. As much as 62% of the overall genetic diversity, measured by an 18S ribosomal barcode, existed in litter and understorey habitats and not in soil. A maximum-likelihood tree of barcodes from 360 individual nematodes indicated most major terrestrial nematode lineages were represented in the samples. Estimated 'species' richness ranged from 464 to 502 within the four 40 x 40 m plots. Directed sampling of insects and their associated nematodes produced a second set of barcodes that were not recovered by habitat sampling, yet may constitute a major class of tropical nematode diversity. While the generation of novel nematode barcodes proved relatively easy, their identity remains obscure due to deficiencies in existing taxonomic databases. Specimens of Criconematina, a monophyletic group of soil-dwelling plant-parasitic nematodes were examined in detail to assess the steps necessary for associating barcodes with nominal species. Our results highlight the difficulties associated with studying poorly understood organisms in an understudied ecosystem using a destructive (i.e. barcode) sampling method.
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Affiliation(s)
- T O Powers
- Department of Plant Pathology, University of Nebraska, Lincoln, NE, USA
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215
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Wiens J. The Causes Of Species Richness Patterns Across Space, Time, And Clades And The Role Of “Ecological Limits”. QUARTERLY REVIEW OF BIOLOGY 2011; 86:75-96. [DOI: 10.1086/659883] [Citation(s) in RCA: 215] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Kim KM, Caetano-Anollés G. The proteomic complexity and rise of the primordial ancestor of diversified life. BMC Evol Biol 2011; 11:140. [PMID: 21612591 PMCID: PMC3123224 DOI: 10.1186/1471-2148-11-140] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2011] [Accepted: 05/25/2011] [Indexed: 01/07/2023] Open
Abstract
BACKGROUND The last universal common ancestor represents the primordial cellular organism from which diversified life was derived. This urancestor accumulated genetic information before the rise of organismal lineages and is considered to be either a simple 'progenote' organism with a rudimentary translational apparatus or a more complex 'cenancestor' with almost all essential biological processes. Recent comparative genomic studies support the latter model and propose that the urancestor was similar to modern organisms in terms of gene content. However, most of these studies were based on molecular sequences, which are fast evolving and of limited value for deep evolutionary explorations. RESULTS Here we engage in a phylogenomic study of protein domain structure in the proteomes of 420 free-living fully sequenced organisms. Domains were defined at the highly conserved fold superfamily (FSF) level of structural classification and an iterative phylogenomic approach was used to reconstruct max_set and min_set FSF repertoires as upper and lower bounds of the urancestral proteome. While the functional make up of the urancestral sets was complex, they represent only 5-11% of the 1,420 FSFs of extant proteomes and their make up and reuse was at least 5 and 3 times smaller than proteomes of free-living organisms, repectively. Trees of proteomes reconstructed directly from FSFs or from molecular functions, which included the max_set and min_set as articial taxa, showed that urancestors were always placed at their base and rooted the tree of life in Archaea. Finally, a molecular clock of FSFs suggests the min_set reflects urancestral genetic make up more reliably and confirms diversified life emerged about 2.9 billion years ago during the start of planet oxygenation. CONCLUSIONS The minimum urancestral FSF set reveals the urancestor had advanced metabolic capabilities, was especially rich in nucleotide metabolism enzymes, had pathways for the biosynthesis of membrane sn1,2 glycerol ester and ether lipids, and had crucial elements of translation, including a primordial ribosome with protein synthesis capabilities. It lacked however fundamental functions, including transcription, processes for extracellular communication, and enzymes for deoxyribonucleotide synthesis. Proteomic history reveals the urancestor is closer to a simple progenote organism but harbors a rather complex set of modern molecular functions.
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Affiliation(s)
- Kyung Mo Kim
- Evolutionary Bioinformatics Laboratory, Department of Crop Science, University of Illinois, Urbana, IL 61801, USA
- Korean Bioinformation Center, Korea Research Institute of Bioscience and Biotechnology, 111 Gwahangno, Yuseong-gu, Daejeon 305-806, Korea
| | - Gustavo Caetano-Anollés
- Evolutionary Bioinformatics Laboratory, Department of Crop Science, University of Illinois, Urbana, IL 61801, USA
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217
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Jones M, Ghoorah A, Blaxter M. jMOTU and Taxonerator: turning DNA Barcode sequences into annotated operational taxonomic units. PLoS One 2011; 6:e19259. [PMID: 21541350 PMCID: PMC3081837 DOI: 10.1371/journal.pone.0019259] [Citation(s) in RCA: 127] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2010] [Accepted: 03/31/2011] [Indexed: 11/23/2022] Open
Abstract
Background DNA barcoding and other DNA sequence-based techniques for investigating and
estimating biodiversity require explicit methods for associating individual
sequences with taxa, as it is at the taxon level that biodiversity is
assessed. For many projects, the bioinformatic analyses required pose
problems for laboratories whose prime expertise is not in bioinformatics.
User-friendly tools are required for both clustering sequences into
molecular operational taxonomic units (MOTU) and for associating these MOTU
with known organismal taxonomies. Results Here we present jMOTU, a Java program for the analysis of DNA barcode
datasets that uses an explicit, determinate algorithm to define MOTU. We
demonstrate its usefulness for both individual specimen-based Sanger
sequencing surveys and bulk-environment metagenetic surveys using long-read
next-generation sequencing data. jMOTU is driven through a graphical user
interface, and can analyse tens of thousands of sequences in a short time on
a desktop computer. A companion program, Taxonerator, that adds traditional
taxonomic annotation to MOTU, is also presented. Clustering and taxonomic
annotation data are stored in a relational database, and are thus amenable
to subsequent data mining and web presentation. Conclusions jMOTU efficiently and robustly identifies the molecular taxa present in
survey datasets, and Taxonerator decorates the MOTU with putative
identifications. jMOTU and Taxonerator are freely available from http://www.nematodes.org/.
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Affiliation(s)
- Martin Jones
- Institute of Evolutionary Biology, University of Edinburgh, Edinburgh,
United Kingdom
| | - Anisah Ghoorah
- Institute of Evolutionary Biology, University of Edinburgh, Edinburgh,
United Kingdom
| | - Mark Blaxter
- Institute of Evolutionary Biology, University of Edinburgh, Edinburgh,
United Kingdom
- * E-mail:
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218
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Fierer N, Lennon JT. The generation and maintenance of diversity in microbial communities. AMERICAN JOURNAL OF BOTANY 2011; 98:439-48. [PMID: 21613137 DOI: 10.3732/ajb.1000498] [Citation(s) in RCA: 130] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Microorganisms play a central role in the regulation of ecosystem processes, and they comprise the vast majority of species on Earth. With recent developments in molecular methods, it has become tractable to quantify the extent of microbial diversity in natural environments. Here we examine this revolution in our understanding of microbial diversity, and we explore the factors that contribute to the seemingly astounding numbers of microbial taxa found within individual environmental samples. We conducted a meta-analysis of bacterial richness estimates from a variety of ecosystems. Nearly all environments contained hundreds to thousands of bacterial taxa, and richness levels increased with the number of individuals in a sample, a pattern consistent with those reported for nonmicrobial taxa. A cursory comparison might suggest that bacterial richness far exceeds the richness levels typically observed for plant and animal taxa. However, the apparent diversity of bacterial communities is influenced by phylogenetic breadth and allometric scaling issues. When these features are taken into consideration, the levels of microbial diversity may appear less astounding. Although the fields of ecology and biogeography have traditionally ignored microorganisms, there are no longer valid excuses for neglecting microorganisms in surveys of biodiversity. Many of the concepts developed to explain plant and animal diversity patterns can also be applied to microorganisms once we reconcile the scale of our analyses to the scale of the organisms being observed. Furthermore, knowledge from microbial systems may provide insight into the mechanisms that generate and maintain species richness in nonmicrobial systems.
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Affiliation(s)
- Noah Fierer
- Cooperative Institute for Research in Environmental Sciences, UCB 216, University of Colorado, Boulder, Colorado 80309, USA.
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219
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Loehle C. Complexity and the problem of ill-posed questions in ecology. ECOLOGICAL COMPLEXITY 2011. [DOI: 10.1016/j.ecocom.2010.11.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Abstract
Understanding how disturbance affects biodiversity is important for both fundamental and applied reasons. Here, I investigate how disturbances with different ecological effects change biodiversity metrics. I define three main types of disturbance effects: D disturbance (shifts in mortality rate), B disturbance (shifts in reproductive rates) and K disturbance (shifts in carrying capacity). Numerous composite disturbances can be defined including any combination of these three types of ecological effects. The consequences of D, B and K disturbances, as well as of composite DBK disturbances are examined by comparing metrics before and after a disturbance, in disturbed and undisturbed communities. I use simulations of neutral communities and examine species richness, total abundance and species abundance distributions. The patterns of change in biodiversity metrics are consistent among different types of disturbance. K disturbance has the most severe effects, followed by D disturbance, and B disturbance has nearly negligible effects. Consequences of composite DBK disturbances are more complex than any of the three types of disturbance, with unimodal relationships along a disturbance gradient arising when D, B and K are negatively correlated. Importantly, regardless of disturbance type, community isolation enhances the negative consequences and hinders the positive effects of disturbances.
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Affiliation(s)
- Maria Dornelas
- ARC Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, Queensland 4811, Australia.
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Staudacher K, Wallinger C, Schallhart N, Traugott M. Detecting ingested plant DNA in soil-living insect larvae. SOIL BIOLOGY & BIOCHEMISTRY 2011; 43:346-350. [PMID: 21317975 PMCID: PMC3021716 DOI: 10.1016/j.soilbio.2010.10.022] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/12/2010] [Revised: 10/26/2010] [Accepted: 10/28/2010] [Indexed: 05/30/2023]
Abstract
Although a significant proportion of plant tissue is located in roots and other below-ground parts of plants, little is known on the dietary choices of root-feeding insects. This is caused by a lack of adequate methodology which would allow tracking below-ground trophic interactions between insects and plants. Here, we present a DNA-based approach to examine this relationship. Feeding experiments were established where either wheat (Triticum aestivum) or maize (Zea mays) was fed to Agriotes larvae (Coleoptera: Elateridae), allowing them to digest for up to 72 h. Due to the very small amount of plant tissue ingested (max = 6.76 mg), DNA extraction procedures and the sensitivity of polymerase chain reaction (PCR) had to be optimized. Whole-body DNA extracts of larvae were tested for the presence of both rbcL and trnL plastid DNA using universal primers. Moreover, based on cpDNA sequences encoding chloroplast tRNA for leucine (trnL), specific primers for maize and wheat were developed. With both, general and specific primers, plant DNA was detectable in the guts of Agriotes larvae for up to 72 h post-feeding, the maximum time of digestion in these experiments. No significant effect of time since feeding on plant DNA detection success was observed, except for the specific primers in maize-fed larvae. Here, plant DNA detection was negatively correlated with the duration of digestion. Both, meal size and initial mass of the individual larvae did not affect the rate of larvae testing positive for plant DNA. The outcomes of this study represent a first step towards a specific analysis of the dietary choices of soil-living herbivores to further increase our understanding of animal-plant feeding interactions in the soil.
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Affiliation(s)
| | - Corinna Wallinger
- Corresponding author. Tel.: +43 (0) 512 507 5687; fax: +43 (0) 512 507 6190.
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BORGES † PAULOA, GABRIEL † ROSALINA, ARROZ † ANAM, COSTA † ANA, CUNHA † REGINAT, SILVA † LUÍS, MENDONÇA † ENÉSIMA, MARTINS † ANTÓNIOMF, REIS † FRANCISCO, CARDOSO † PEDRO. The Azorean Biodiversity Portal: An internet database for regional biodiversity outreach. SYST BIODIVERS 2010. [DOI: 10.1080/14772000.2010.514306] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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225
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Mielke OHH, Carneiro E, Casagrande MM. Lepidopterofauna (Papilionoidea e Hesperioidea) do Parque Estadual do Chandless e arredores, Acre, Brasil. BIOTA NEOTROPICA 2010. [DOI: 10.1590/s1676-06032010000400033] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Tendo em vista a ausência de inventários lepidopterológicos no Estado do Acre e sua escassez no bioma amazônico brasileiro, o presente estudo objetivou contribuir para a construção da lista de Hesperioidea e Papilionoidea presentes no Parque Estadual do Chandless, localizado em uma região de difícil acesso e sem infra-estrutura para pesquisa científica. Durante 14 dias foram realizadas coletas com redes entomológicas, armadilhas e técnica de Ahrenholz em diferentes ambientes que caracterizam o parque e seus arredores. Foram identificadas ao total 482 espécies, nenhuma delas presente em listas vermelhas de espécies ameaçadas. É esperado um número significativamente maior de espécies após a adição de novas coletas em outras estações do ano, visto a estimativa Jacknife 1 não atingir sua assíntota, ou mesmo em comparação a inventários em áreas próximas que listam, após um intenso esforço amostral, até cerca de 1700 espécies.
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226
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Von Der Heyden S. ‘Carry on sampling!’- assessing marine fish biodiversity and discovery rates in southern Africa. DIVERS DISTRIB 2010. [DOI: 10.1111/j.1472-4642.2010.00712.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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Fonseca VG, Carvalho GR, Sung W, Johnson HF, Power DM, Neill SP, Packer M, Blaxter ML, Lambshead PJD, Thomas WK, Creer S. Second-generation environmental sequencing unmasks marine metazoan biodiversity. Nat Commun 2010; 1:98. [PMID: 20981026 PMCID: PMC2963828 DOI: 10.1038/ncomms1095] [Citation(s) in RCA: 194] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2010] [Accepted: 09/22/2010] [Indexed: 11/22/2022] Open
Abstract
Biodiversity is of crucial importance for ecosystem functioning, sustainability and resilience, but the magnitude and organization of marine diversity at a range of spatial and taxonomic scales are undefined. In this paper, we use second-generation sequencing to unmask putatively diverse marine metazoan biodiversity in a Scottish temperate benthic ecosystem. We show that remarkable differences in diversity occurred at microgeographical scales and refute currently accepted ecological and taxonomic paradigms of meiofaunal identity, rank abundance and concomitant understanding of trophic dynamics. Richness estimates from the current benchmarked Operational Clustering of Taxonomic Units from Parallel UltraSequencing analyses are broadly aligned with those derived from morphological assessments. However, the slope of taxon rarefaction curves for many phyla remains incomplete, suggesting that the true alpha diversity is likely to exceed current perceptions. The approaches provide a rapid, objective and cost-effective taxonomic framework for exploring links between ecosystem structure and function of all hitherto intractable, but ecologically important, communities. Recent developments in sequencing technologies have provided the opportunity to investigate the biodiversity of ecosystems. Such a metagenomic approach, combined with taxon clustering, is used here to demonstrate that the species richness of a marine community in Scotland is much greater than anticipated.
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Affiliation(s)
- Vera G Fonseca
- Molecular Ecology and Fisheries Genetics Laboratory, School of Biological Sciences, Environment Centre Wales, Bangor University, Deiniol Road, Gwynedd LL57 2UW, UK
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228
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Hamilton AJ, Basset Y, Benke KK, Grimbacher PS, Miller SE, Novotný V, Samuelson GA, Stork NE, Weiblen GD, Yen JDL. Quantifying uncertainty in estimation of tropical arthropod species richness. Am Nat 2010; 176:90-5. [PMID: 20455708 DOI: 10.1086/652998] [Citation(s) in RCA: 100] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
There is a bewildering range of estimates for the number of arthropods on Earth. Several measures are based on extrapolation from species specialized to tropical rain forest, each using specific assumptions and justifications. These approaches have not provided any sound measure of uncertainty associated with richness estimates. We present two models that account for parameter uncertainty by replacing point estimates with probability distributions. The models predict medians of 3.7 million and 2.5 million tropical arthropod species globally, with 90% confidence intervals of [2.0, 7.4] million and [1.1, 5.4] million, respectively. Estimates of 30 million or greater are predicted to have <0.00001 probability. Sensitivity analyses identified uncertainty in the proportion of canopy arthropod species that are beetles as the most influential parameter, although uncertainties associated with three other parameters were also important. Using the median estimates suggests that in spite of 250 years of taxonomy and around 855,000 species of arthropods already described, approximately 70% await description.
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Affiliation(s)
- Andrew J Hamilton
- Department of Resource Management and Geography, University of Melbourne, Burnley Campus, 500 Yarra Boulevard, Richmond, Victoria 3121, Australia.
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229
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Harris NC, Dunn RR. Using host associations to predict spatial patterns in the species richness of the parasites of North American carnivores. Ecol Lett 2010; 13:1411-8. [DOI: 10.1111/j.1461-0248.2010.01527.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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230
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Abstract
We estimate the probable number of flowering plants. First, we apply a model that explicitly incorporates taxonomic effort over time to estimate the number of as-yet-unknown species. Second, we ask taxonomic experts their opinions on how many species are likely to be missing, on a family-by-family basis. The results are broadly comparable. We show that the current number of species should grow by between 10 and 20 per cent. There are, however, interesting discrepancies between expert and model estimates for some families, suggesting that our model does not always completely capture patterns of taxonomic activity. The as-yet-unknown species are probably similar to those taxonomists have described recently—overwhelmingly rare and local, and disproportionately in biodiversity hotspots, where there are high levels of habitat destruction.
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Affiliation(s)
- Lucas N Joppa
- Microsoft Research, 7 J J Thomson Avenue, Cambridge CB3 0FB, UK
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231
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Abstract
Recent extinction rates are 100 to 1000 times their pre-human levels in well-known, but taxonomically diverse groups from widely different environments. If all species currently deemed "threatened" become extinct in the next century, then future extinction rates will be 10 times recent rates. Some threatened species will survive the century, but many species not now threatened will succumb. Regions rich in species found only within them (endemics) dominate the global patterns of extinction. Although new technology provides details of habitat losses, estimates of future extinctions are hampered by our limited knowledge of which areas are rich in endemics.
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232
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Abstract
Fragmentation of habitats in the agricultural landscape is a major threat to biological diversity, which is greatly determined by insects. Isolation of habitat fragments resulted in decreased numbers of species as well as reduced effects of natural enemies. Manually established islands of red clover were colonized by most available herbivore species but few parasitoid species. Thus, herbivores were greatly released from parasitism, experiencing only 19 to 60 percent of the parasitism of nonisolated populations. Species failing to successfully colonize isolated islands were characterized by small and highly variable populations. Accordingly, lack of habitat connectivity released insects from predator control.
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233
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Abstract
Biodiversity studies comprise the systematic examination of the full array of different kinds of organisms together with the technology by which the diversity can be maintained and used for the benefit of humanity. Current basic research at the species level focuses on the process of species formation, the standing levels of species numbers in various higher taxonomic categories, and the phenomena of hyperdiversity and extinction proneness. The major practical concern is the massive extinction rate now caused by human activity, which threatens losses in the esthetic quality of the world, in economic opportunity, and in vital ecosystem services.
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234
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235
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Abstract
A central problem in ecology is predicting the diversity of communities. Insect parasitoids may encompass 20 percent of all insect species; hence, establishing the mechanisms that drive parasitoid species richness represents a major step in understanding the diversity of terrestrial communities. An assemblage model, based on population dynamic constructs, shows how the presence of refuges from parasitoid attack can generate diversity patterns that are in good accord with global data on structural protection from parasitism resulting from host feeding biology. This theory offers a simple ecological explanation for the range of diversities observed in real parasitoid assemblages. Predicting parasitoid diversity may be a realistic goal, at least for those systems in which the basic demography is well understood.
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236
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Tolimieri N, Anderson MJ. Taxonomic distinctness of demersal fishes of the California current: moving beyond simple measures of diversity for marine ecosystem-based management. PLoS One 2010; 5:e10653. [PMID: 20498727 PMCID: PMC2871800 DOI: 10.1371/journal.pone.0010653] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2010] [Accepted: 04/25/2010] [Indexed: 11/26/2022] Open
Abstract
Background Large-scale patterns or trends in species diversity have long interested ecologists. The classic pattern is for diversity (e.g., species richness) to decrease with increasing latitude. Taxonomic distinctness is a diversity measure based on the relatedness of the species within a sample. Here we examined patterns of taxonomic distinctness in relation to latitude (ca. 32–48 °N) and depth (ca. 50–1220 m) for demersal fishes on the continental shelf and slope of the US Pacific coast. Methodology/Principal Findings Both average taxonomic distinctness (AvTD) and variation in taxonomic distinctness (VarTD) changed with latitude and depth. AvTD was highest at approximately 500 m and lowest at around 200 m bottom depth. Latitudinal trends in AvTD were somewhat weaker and were depth-specific. AvTD increased with latitude on the shelf (50–150 m) but tended to decrease with latitude at deeper depths. Variation in taxonomic distinctness (VarTD) was highest around 300 m. As with AvTD, latitudinal trends in VarTD were depth-specific. On the shelf (50–150 m), VarTD increased with latitude, while in deeper areas the patterns were more complex. Closer inspection of the data showed that the number and distribution of species within the class Chondrichthyes were the primary drivers of the overall patterns seen in AvTD and VarTD, while the relatedness and distribution of species in the order Scorpaeniformes appeared to cause the relatively low observed values of AvTD at around 200 m. Conclusions/Significance These trends contrast to some extent the patterns seen in earlier studies for species richness and evenness in demersal fishes along this coast and add to our understanding of diversity of the demersal fishes of the California Current.
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Affiliation(s)
- Nick Tolimieri
- National Oceanic and Atmospheric Administration, Northwest Fisheries Science Center, Seattle, Washington, United States of America.
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237
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Estimated evolutionary tempo of East Asian gobionid fishes (Teleostei: Cyprinidae) from mitochondrial DNA sequence data. CHINESE SCIENCE BULLETIN-CHINESE 2010. [DOI: 10.1007/s11434-010-3159-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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238
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Donoso DA, Johnston MK, Kaspari M. Trees as templates for tropical litter arthropod diversity. Oecologia 2010; 164:201-11. [DOI: 10.1007/s00442-010-1607-3] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2009] [Accepted: 02/17/2010] [Indexed: 11/28/2022]
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239
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240
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Baselga A, Lobo JM, Hortal J, Jiménez-Valverde A, Gómez JF. Assessingalphaandbetataxonomy in eupelmid wasps: determinants of the probability of describing good species and synonyms. J ZOOL SYST EVOL RES 2010. [DOI: 10.1111/j.1439-0469.2009.00523.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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241
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NERES PATRICIAFERNANDES, DA FONSECA-GENEVOIS VERÔNICAGOMES, TORRES RODRIGOAUGUSTO, DA FONSECA CAVALCANTI MARIANA, DE CASTRO FRANCISCOJOSÉVICTOR, DA SILVA NEYVANRENATORODRIGUES, RIEGER TANIATASSINARI, DECRAEMER WILFRIDA. Morphological and molecular taxonomy of a newDaptonema(Nematoda, Xyalidae) with comments on the systematics of some related taxa. Zool J Linn Soc 2010. [DOI: 10.1111/j.1096-3642.2009.00528.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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242
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O'Gorman EJ, Emmerson MC. Manipulating Interaction Strengths and the Consequences for Trivariate Patterns in a Marine Food Web. ADV ECOL RES 2010. [DOI: 10.1016/b978-0-12-381363-3.00006-x] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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243
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Kaltenpoth M. Actinobacteria as mutualists: general healthcare for insects? Trends Microbiol 2009; 17:529-35. [DOI: 10.1016/j.tim.2009.09.006] [Citation(s) in RCA: 159] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2009] [Revised: 09/25/2009] [Accepted: 09/30/2009] [Indexed: 02/03/2023]
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244
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Biological collections and ecological/environmental research: a review, some observations and a look to the future. Biol Rev Camb Philos Soc 2009; 85:247-66. [PMID: 19961469 DOI: 10.1111/j.1469-185x.2009.00098.x] [Citation(s) in RCA: 144] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Housed worldwide, mostly in museums and herbaria, is a vast collection of biological specimens developed over centuries. These biological collections, and associated taxonomic and systematic research, have received considerable long-term public support. The work remaining in systematics has been expanding as the estimated total number of species of organisms on Earth has risen over recent decades, as have estimated numbers of undescribed species. Despite this increasing task, support for taxonomic and systematic research, and biological collections upon which such research is based, has declined over the last 30-40 years, while other areas of biological research have grown considerably, especially those that focus on environmental issues. Reflecting increases in research that deals with ecological questions (e.g. what determines species distribution and abundance) or environmental issues (e.g. toxic pollution), the level of research attempting to use biological collections in museums or herbaria in an ecological/environmental context has risen dramatically during about the last 20 years. The perceived relevance of biological collections, and hence the support they receive, should be enhanced if this trend continues and they are used prominently regarding such environmental issues as anthropogenic loss of biodiversity and associated ecosystem function, global climate change, and decay of the epidemiological environment. It is unclear, however, how best to use biological collections in the context of such ecological/environmental issues or how best to manage collections to facilitate such use. We demonstrate considerable and increasingly realized potential for research based on biological collections to contribute to ecological/environmental understanding. However, because biological collections were not originally intended for use regarding such issues and have inherent biases and limitations, they are proving more useful in some contexts than in others. Biological collections have, for example, been particularly useful as sources of information regarding variation in attributes of individuals (e.g. morphology, chemical composition) in relation to environmental variables, and provided important information in relation to species' distributions, but less useful in the contexts of habitat associations and population sizes. Changes to policies, strategies and procedures associated with biological collections could mitigate these biases and limitations, and hence make such collections more useful in the context of ecological/environmental issues. Haphazard and opportunistic collecting could be replaced with strategies for adding to existing collections that prioritize projects that use biological collections and include, besides taxonomy and systematics, a focus on significant environmental/ecological issues. Other potential changes include increased recording of the nature and extent of collecting effort and information associated with each specimen such as nearby habitat and other individuals observed but not collected. Such changes have begun to occur within some institutions. Institutions that house biological collections should, we think, pursue a mission of 'understanding the life of the planet to inform its stewardship' (Krishtalka & Humphrey, 2000), as such a mission would facilitate increased use of biological collections in an ecological/environmental context and hence lead to increased appreciation, encouragement and support from the public for these collections, their associated research, and the institutions that house them.
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245
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Genome 10K: a proposal to obtain whole-genome sequence for 10,000 vertebrate species. J Hered 2009; 100:659-74. [PMID: 19892720 PMCID: PMC2877544 DOI: 10.1093/jhered/esp086] [Citation(s) in RCA: 371] [Impact Index Per Article: 24.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2009] [Revised: 09/21/2009] [Accepted: 09/22/2009] [Indexed: 01/13/2023] Open
Abstract
The human genome project has been recently complemented by whole-genome assessment sequence of 32 mammals and 24 nonmammalian vertebrate species suitable for comparative genomic analyses. Here we anticipate a precipitous drop in costs and increase in sequencing efficiency, with concomitant development of improved annotation technology and, therefore, propose to create a collection of tissue and DNA specimens for 10,000 vertebrate species specifically designated for whole-genome sequencing in the very near future. For this purpose, we, the Genome 10K Community of Scientists (G10KCOS), will assemble and allocate a biospecimen collection of some 16,203 representative vertebrate species spanning evolutionary diversity across living mammals, birds, nonavian reptiles, amphibians, and fishes (ca. 60,000 living species). In this proposal, we present precise counts for these 16,203 individual species with specimens presently tagged and stipulated for DNA sequencing by the G10KCOS. DNA sequencing has ushered in a new era of investigation in the biological sciences, allowing us to embark for the first time on a truly comprehensive study of vertebrate evolution, the results of which will touch nearly every aspect of vertebrate biological enquiry.
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246
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Kosakovsky Pond S, Wadhawan S, Chiaromonte F, Ananda G, Chung WY, Taylor J, Nekrutenko A. Windshield splatter analysis with the Galaxy metagenomic pipeline. Genome Res 2009; 19:2144-53. [PMID: 19819906 DOI: 10.1101/gr.094508.109] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
How many species inhabit our immediate surroundings? A straightforward collection technique suitable for answering this question is known to anyone who has ever driven a car at highway speeds. The windshield of a moving vehicle is subjected to numerous insect strikes and can be used as a collection device for representative sampling. Unfortunately the analysis of biological material collected in that manner, as with most metagenomic studies, proves to be rather demanding due to the large number of required tools and considerable computational infrastructure. In this study, we use organic matter collected by a moving vehicle to design and test a comprehensive pipeline for phylogenetic profiling of metagenomic samples that includes all steps from processing and quality control of data generated by next-generation sequencing technologies to statistical analyses and data visualization. To the best of our knowledge, this is also the first publication that features a live online supplement providing access to exact analyses and workflows used in the article.
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247
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Brüssow H. The not so universal tree of life or the place of viruses in the living world. Philos Trans R Soc Lond B Biol Sci 2009; 364:2263-74. [PMID: 19571246 DOI: 10.1098/rstb.2009.0036] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Darwin provided a great unifying theory for biology; its visual expression is the universal tree of life. The tree concept is challenged by the occurrence of horizontal gene transfer and-as summarized in this review -- by the omission of viruses. Microbial ecologists have demonstrated that viruses are the most numerous biological entities on earth, outnumbering cells by a factor of 10. Viral genomics have revealed an unexpected size and distinctness of the viral DNA sequence space. Comparative genomics has shown elements of vertical evolution in some groups of viruses. Furthermore, structural biology has demonstrated links between viruses infecting the three domains of life pointing to a very ancient origin of viruses. However, presently viruses do not find a place on the universal tree of life, which is thus only a tree of cellular life. In view of the polythetic nature of current life definitions, viruses cannot be dismissed as non-living material. On earth we have therefore at least two large DNA sequence spaces, one represented by capsid-encoding viruses and another by ribosome-encoding cells. Despite their probable distinct evolutionary origin, both spheres were and are connected by intensive two-way gene transfers.
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Affiliation(s)
- Harald Brüssow
- Chemin de la Chaumény 13, La Tour de Peilz, Switzerland.
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248
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Krüger O, Sorenson MD, Davies NB. Does coevolution promote species richness in parasitic cuckoos? Proc Biol Sci 2009; 276:3871-9. [PMID: 19692405 PMCID: PMC2817292 DOI: 10.1098/rspb.2009.1142] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Why some lineages have diversified into larger numbers of species than others is a fundamental but still relatively poorly understood aspect of the evolutionary process. Coevolution has been recognized as a potentially important engine of speciation, but has rarely been tested in a comparative framework. We use a comparative approach based on a complete phylogeny of all living cuckoos to test whether parasite–host coevolution is associated with patterns of cuckoo species richness. There are no clear differences between parental and parasitic cuckoos in the number of species per genus. However, a cladogenesis test shows that brood parasitism is associated with both significantly higher speciation and extinction rates. Furthermore, subspecies diversification rate estimates were over twice as high in parasitic cuckoos as in parental cuckoos. Among parasitic cuckoos, there is marked variation in the severity of the detrimental effects on host fitness; chicks of some cuckoo species are raised alongside the young of the host and others are more virulent, with the cuckoo chick ejecting or killing the eggs/young of the host. We show that cuckoos with a more virulent parasitic strategy have more recognized subspecies. In addition, cuckoo species with more recognized subspecies have more hosts. These results hold after controlling for confounding geographical effects such as range size and isolation in archipelagos. Although the power of our analyses is limited by the fact that brood parasitism evolved independently only three times in cuckoos, our results suggest that coevolutionary arms races with hosts have contributed to higher speciation and extinction rates in parasitic cuckoos.
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Affiliation(s)
- Oliver Krüger
- Department of Zoology, University of Cambridge, Cambridge, UK.
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249
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Barcoding Antarctic Biodiversity: current status and the CAML initiative, a case study of marine invertebrates. Polar Biol 2009. [DOI: 10.1007/s00300-009-0662-x] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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250
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