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Polato NR, Gray MM, Gill BA, Becker CG, Casner KL, Flecker AS, Kondratieff BC, Encalada AC, Poff NL, Funk WC, Zamudio KR. Genetic diversity and gene flow decline with elevation in montane mayflies. Heredity (Edinb) 2017; 119:107-116. [PMID: 28489073 DOI: 10.1038/hdy.2017.23] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2016] [Revised: 03/25/2017] [Accepted: 03/27/2017] [Indexed: 01/15/2023] Open
Abstract
Montane environments around the globe are biodiversity 'hotspots' and important reservoirs of genetic diversity. Montane species are also typically more vulnerable to environmental change than their low-elevation counterparts due to restricted ranges and dispersal limitations. Here we focus on two abundant congeneric mayflies (Baetis bicaudatus and B. tricaudatus) from montane streams over an elevation gradient spanning 1400 m. Using single-nucleotide polymorphism genotypes, we measured population diversity and vulnerability in these two species by: (i) describing genetic diversity and population structure across elevation gradients to identify mechanisms underlying diversification; (ii) performing spatially explicit landscape analyses to identify environmental drivers of differentiation; and (iii) identifying outlier loci hypothesized to underlie adaptive divergence. Differences in the extent of population structure in these species were evident depending upon their position along the elevation gradient. Heterozygosity, effective population sizes and gene flow all declined with increasing elevation, resulting in substantial population structure in the higher elevation species (B. bicaudatus). At lower elevations, populations of both species are more genetically similar, indicating ongoing gene flow. Isolation by distance was detected at lower elevations only, whereas landscape barriers better predicted genetic distance at higher elevations. At higher elevations, dispersal was restricted due to landscape effects, resulting in greater population isolation. Our results demonstrate differentiation over small spatial scales along an elevation gradient, and highlight the importance of preserving genetic diversity in more isolated high-elevation populations.
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Affiliation(s)
- N R Polato
- Department of Ecology and Evolutionary Biology, Cornell University, Ithaca, NY, USA
| | - M M Gray
- Department of Ecology and Evolutionary Biology, Cornell University, Ithaca, NY, USA
| | - B A Gill
- Department of Biology, Colorado State University, Fort Collins, Colorado, USA
| | - C G Becker
- Departamento de Zoologia, Universidade Estadual Paulista, Rio Claro, Brazil
| | - K L Casner
- Department of Biology, Colorado State University, Fort Collins, Colorado, USA
| | - A S Flecker
- Department of Ecology and Evolutionary Biology, Cornell University, Ithaca, NY, USA
| | - B C Kondratieff
- Department of Biology, Colorado State University, Fort Collins, Colorado, USA
| | - A C Encalada
- Colegio de Ciencias Biológicas y Ambientales, Universidad San Francisco de Quito, Quito, Ecuador
| | - N L Poff
- Department of Biology, Colorado State University, Fort Collins, Colorado, USA.,Institute of Applied Ecology, University of Canberra, ACT 2617, Australia
| | - W C Funk
- Department of Biology, Colorado State University, Fort Collins, Colorado, USA
| | - K R Zamudio
- Department of Ecology and Evolutionary Biology, Cornell University, Ithaca, NY, USA
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Gill BA, Kondratieff BC, Casner KL, Encalada AC, Flecker AS, Gannon DG, Ghalambor CK, Guayasamin JM, Poff NL, Simmons MP, Thomas SA, Zamudio KR, Funk WC. Cryptic species diversity reveals biogeographic support for the 'mountain passes are higher in the tropics' hypothesis. Proc Biol Sci 2016; 283:20160553. [PMID: 27306051 PMCID: PMC4920318 DOI: 10.1098/rspb.2016.0553] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2016] [Accepted: 05/18/2016] [Indexed: 01/30/2023] Open
Abstract
The 'mountain passes are higher in the tropics' (MPHT) hypothesis posits that reduced climate variability at low latitudes should select for narrower thermal tolerances, lower dispersal and smaller elevational ranges compared with higher latitudes. These latitudinal differences could increase species richness at low latitudes, but that increase may be largely cryptic, because physiological and dispersal traits isolating populations might not correspond to morphological differences. Yet previous tests of the MPHT hypothesis have not addressed cryptic diversity. We use integrative taxonomy, combining morphology (6136 specimens) and DNA barcoding (1832 specimens) to compare the species richness, cryptic diversity and elevational ranges of mayflies (Ephemeroptera) in the Rocky Mountains (Colorado; approx. 40°N) and the Andes (Ecuador; approx. 0°). We find higher species richness and smaller elevational ranges in Ecuador than Colorado, but only after quantifying and accounting for cryptic diversity. The opposite pattern is found when comparing diversity based on morphology alone, underscoring the importance of uncovering cryptic species to understand global biodiversity patterns.
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Affiliation(s)
- B A Gill
- Department of Biology, Colorado State University, Fort Collins, CO 80523, USA Graduate Degree Program in Ecology, Colorado State University, Fort Collins, CO 80523, USA
| | - B C Kondratieff
- Graduate Degree Program in Ecology, Colorado State University, Fort Collins, CO 80523, USA Department of Bioagricultural Sciences and Pest Management, Colorado State University, Fort Collins, CO 80523, USA
| | - K L Casner
- Department of Biology, Colorado State University, Fort Collins, CO 80523, USA
| | - A C Encalada
- Colegio de Ciencias Biológicas y Ambientales, Universidad San Francisco de Quito, Diego de Robles y Vía Interoceánica, 17-1200-841 Quito, Ecuador
| | - A S Flecker
- Department of Ecology and Evolutionary Biology, Cornell University, Ithaca, NY 14853, USA
| | - D G Gannon
- Department of Biology, Colorado State University, Fort Collins, CO 80523, USA
| | - C K Ghalambor
- Department of Biology, Colorado State University, Fort Collins, CO 80523, USA Graduate Degree Program in Ecology, Colorado State University, Fort Collins, CO 80523, USA
| | - J M Guayasamin
- Colegio de Ciencias Biológicas y Ambientales, Universidad San Francisco de Quito, Diego de Robles y Vía Interoceánica, 17-1200-841 Quito, Ecuador Centro de Investigación de la Biodiversidad y Cambio Climático, Ingeniería en Biodiversidad y Recursos Genéticos, Facultad de Ciencias de Medio Ambiente, Universidad Tecnológica Indoamérica, Calle Machala y Sabanilla, Quito, Ecuador
| | - N L Poff
- Department of Biology, Colorado State University, Fort Collins, CO 80523, USA Graduate Degree Program in Ecology, Colorado State University, Fort Collins, CO 80523, USA
| | - M P Simmons
- Department of Biology, Colorado State University, Fort Collins, CO 80523, USA
| | - S A Thomas
- School of Natural Resources, University of Nebraska, Lincoln, NE 68583, USA
| | - K R Zamudio
- Department of Ecology and Evolutionary Biology, Cornell University, Ithaca, NY 14853, USA
| | - W C Funk
- Department of Biology, Colorado State University, Fort Collins, CO 80523, USA Graduate Degree Program in Ecology, Colorado State University, Fort Collins, CO 80523, USA
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Rose DA, Kondratieff BC, Weissmann MJ. New State Records of Mosquitoes for Colorado. J Am Mosq Control Assoc 2015; 31:135-138. [PMID: 26181688 DOI: 10.2987/15-6482r] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The 1967 treatment of the Mosquitoes of Colorado by Harmston and Lawson and subsequent publications have recorded 46 culicid species from Colorado. As part of a study to create an updated synopsis of the mosquitoes of Colorado, adult trapping at numerous localities was conducted in Colorado during the summers of 2013 and 2014. This review also included an examination of mosquito specimens in various relevant museum collections. Aedes (Ochlerotatus) niphadopsis and Ae. (Och.) spencerii spencerii were collected during the 2013 and 2014 field seasons. Records for Ae. (Och.) canadensis canadensis, Ae. (Stegomyia) aegypti, and Uranotaenia (Pseudoficalbia) anhydor syntheta were obtained from examination of museum specimens. These species constitute new state records for Colorado, with 51 species now known from the state.
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Affiliation(s)
- Dominic A Rose
- 1 Colorado State University, Department of Bioagricultural Sciences, Pest Management, Fort Collins, CO 80523-1177
- 2 Colorado Mosquito Control, Inc., 7000 Broadway, Suite 108, Denver, CO 80221
| | - B C Kondratieff
- 1 Colorado State University, Department of Bioagricultural Sciences, Pest Management, Fort Collins, CO 80523-1177
| | - M J Weissmann
- 2 Colorado Mosquito Control, Inc., 7000 Broadway, Suite 108, Denver, CO 80221
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Affiliation(s)
- Sen-Her Shieh
- Department of Biology, Colorado State University, Fort Collins, Colorado 80523 USA
| | - J. V. Ward
- Department of Limnology, EAWAG/ETH, Überlandstrasse 133, CH-8600 Dübendorf, Switzerland
| | - B. C. Kondratieff
- Department of Bioagricultural Science and Pest Management, Colorado State University, Fort Collins, Colorado 80523 USA
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