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Lustri L, Laibl L, Bicknell RD. A revision of Prolimulus woodwardi Fritsch, 1899 with comparison to other highly paedomorphic belinurids. PeerJ 2021; 9:e10980. [PMID: 33732551 PMCID: PMC7950201 DOI: 10.7717/peerj.10980] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Accepted: 01/30/2021] [Indexed: 01/02/2023] Open
Abstract
Xiphosurida is an ingroup of marine Euchelicerata often referred to as "living fossils". However, this oxymoronic term is inapplicable for Paleozoic and early Mesozoic forms, as during these periods the group experienced notable evolutionary radiations; particularly the diverse late Palaeozoic clade Belinurina. Despite the iconic nature of the group, select species in this clade have been left undescribed in the light of recent geometric morphometric and phylogenetic considerations and methodologies. To this end, we re-describe Prolimulus woodwardi Fritsch, 1899 using new and type specimens to reveal more details on appendage anatomy and possible ecology. Furthermore, we present geometric morphometric and phylogenetic analyses that uncover relationships between P. woodwardi and other belinurids without genal spines. Both approaches highlight that a clade containing Prolimulus Fritsch, 1899, Liomesaspis Raymond, 1944, Alanops Racheboeuf, Vannier & Anderson, 2002 and Stilpnocephalus Selden, Simonetto & Marsiglio, 2019 may exist. While we do not erect a new group to contain these genera, we note that these genera exemplify the extreme limits of the Belinurina radiation and a peak in horseshoe crab diversity and disparity. This evidence also illustrates how changes in heterochronic timing are a key evolutionary phenomenon that can drive radiations among animals.
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Affiliation(s)
- Lorenzo Lustri
- Institute of Earth Sciences, University of Lausanne, Geopolis, Lausanne, Switzerland
| | - Lukáš Laibl
- Institute of Geology and Palaeontology, Faculty of Science, Charles University, Prague, Czech Republic
- Institute of Geology of the Czech Academy of Sciences, Prague, Czech Republic
| | - Russell D.C. Bicknell
- Palaeoscience Research Centre, School of Environmental and Rural Science, University of New England, Armidale, New South Wales, Australia
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Sasson DA, Johnson SL, Smith MD, Brockmann HJ. Seasonal Variation in Reproduction of Horseshoe Crabs ( Limulus polyphemus) from the Gulf Coast of Florida. THE BIOLOGICAL BULLETIN 2020; 239:24-39. [PMID: 32812812 DOI: 10.1086/709876] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
AbstractThe timing of reproduction is often governed by environmental variables, such as temperature or rainfall. Understanding how environmental variables affect mating dynamics is necessary to predict how systems and populations may adapt to changing environmental conditions and is crucial for management of threatened species. The American horseshoe crab (Limulus polyphemus) ranges from the Yucatan to Maine in distinct populations that differ in their timing of reproduction; while most populations have only one breeding period during the spring, some southern populations have two breeding periods. Here we discuss seasonal patterns of reproduction in a Florida Gulf coast population where horseshoe crabs have two periods of breeding: one in the spring and another in the fall. We used environmental measurements, spawning surveys, mark-recapture, and measurements of adult traits and spawning behavior to compare reproductive parameters between the two spawning seasons over three years. We then evaluated whether environmental conditions affect fall and spring horseshoe crab nesting patterns similarly and whether fall and spring horseshoe crabs should be considered two separate populations. We found significant differences in environmental conditions across seasons and in a wide variety of horseshoe crab traits and nesting parameters. Furthermore, environmental conditions affected nesting behaviors of fall and spring horseshoe crabs differently. However, some individuals spawn during both seasons, suggesting that trait differences may be attributable to environmental effects during development or seasonal plasticity, rather than genetic differences, although further study is necessary. Finally, our results suggest that management practices should be tailored to each population, because environmental conditions may have different effects even on genetically similar groups.
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Brockmann HJ, St Mary CM, Ponciano JM. Discovering structural complexity and its causes: Breeding aggregations in horseshoe crabs. Anim Behav 2018. [DOI: 10.1016/j.anbehav.2017.10.020] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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4
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Carcinoscorpius rotundicauda (Latreille, 1802) population status and spawning behaviour at Pendas coast, Peninsular Malaysia. Glob Ecol Conserv 2018. [DOI: 10.1016/j.gecco.2018.e00422] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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5
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Kawase S, Hayashi T, Matsumoto Y, Takegaki T. Testis size variation within sneaker males of the dusky frillgoby Bathygobius fuscus (Gobiidae): effects of within-tactic competition. Biol J Linn Soc Lond 2017. [DOI: 10.1093/biolinnean/blx075] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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6
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Parker GA, Ramm SA, Lehtonen J, Henshaw JM. The evolution of gonad expenditure and gonadosomatic index (GSI) in male and female broadcast-spawning invertebrates. Biol Rev Camb Philos Soc 2017; 93:693-753. [PMID: 28921784 DOI: 10.1111/brv.12363] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2017] [Revised: 07/22/2017] [Accepted: 08/09/2017] [Indexed: 01/05/2023]
Abstract
Sedentary broadcast-spawning marine invertebrates, which release both eggs and sperm into the water for fertilization, are of special interest for sexual selection studies. They provide unique insight into the early stages of the evolutionary succession leading to the often-intense operation of both pre- and post-mating sexual selection in mobile gonochorists. Since they are sessile or only weakly mobile, adults can interact only to a limited extent with other adults and with their own fertilized offspring. They are consequently subject mainly to selection on gamete production and gamete success, and so high gonad expenditure is expected in both sexes. We review literature on gonadosomatic index (GSI; the proportion of body tissue devoted to gamete production) of gonochoristic broadcast spawners, which we use as a proxy for gonad expenditure. We show that such taxa most often have a high GSI that is approximately equal in both sexes. When GSI is asymmetric, female GSI usually exceeds male GSI, at least in echinoderms (the majority of species recorded). Intriguingly, though, higher male GSI also occurs in some species and appears more common than female-biased GSI in certain orders of gastropod molluscs. Our limited data also suggest that higher male GSI may be the prevalent pattern in sperm casters (where only males release gametes). We explore how selection might have shaped these patterns using game theoretic models for gonad expenditure that consider possible trade-offs with (i) somatic maintenance or (ii) growth, while also considering sperm competition, sperm limitation, and polyspermy. Our models of the trade-off between somatic tissue (which increases survival) and gonad (which increases reproductive success) predict that GSI should be equal for the two sexes when sperm competition is intense, as is probably common in broadcast spawners due to synchronous spawning in aggregations. Higher female GSI occurs under low sperm competition. Sperm limitation appears unlikely to alter these conclusions qualitatively, but can also act as a force to keep male GSI high, and close to that of females. Polyspermy can act to reduce male GSI. Higher male than female GSI is predicted to be less common (as observed in the data), but can occur when ova/ovaries are sufficiently more resource-intensive to produce than sperm/testes, for which some evidence exists. We also show that sex-specific trade-offs between gonads and growth can generate different life-history strategies for males and females, with males beginning reproduction earlier. This could lead to apparently higher male GSI in empirical studies if immature females are included in calculations of mean GSI. The existence of higher male GSI nonetheless remains somewhat problematic and requires further investigation. When sperm limitation is low, we suggest that the natural logarithm of the male/female GSI ratio may be a suitable index for sperm competition level in broadcast spawners, and that this may also be considered as an index for internally fertilizing taxa.
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Affiliation(s)
- Geoff A Parker
- Department of Evolution, Ecology and Behaviour, Institute of Integrative Biology, University of Liverpool, Liverpool, L69 7ZB, U.K
| | - Steven A Ramm
- Evolutionary Biology, Bielefeld University, 33615, Bielefeld, Germany
| | - Jussi Lehtonen
- Evolution and Ecology Research Centre, School of Biological, Earth and Environmental Sciences, University of New South Wales, Sydney, 2052, Australia
| | - Jonathan M Henshaw
- Division of Ecology and Evolution, Research School of Biology, The Australian National University, 2601, Canberra, Australia.,Institute of Zoology, University of Graz, Graz, 8010, Austria
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Manca A, Mohamad F, Ahmad A, Afham Mohd Sofa MF, Ismail N. Tri-spine horseshoe crab, Tachypleus tridentatus (L.) in Sabah, Malaysia: the adult body sizes and population estimate. JOURNAL OF ASIA-PACIFIC BIODIVERSITY 2017. [DOI: 10.1016/j.japb.2017.04.011] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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8
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Tanner JC, Ward JL, Shaw RG, Bee MA. Multivariate phenotypic selection on a complex sexual signal. Evolution 2017; 71:1742-1754. [DOI: 10.1111/evo.13264] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2017] [Revised: 04/06/2017] [Accepted: 04/19/2017] [Indexed: 11/27/2022]
Affiliation(s)
- Jessie C. Tanner
- Department of Ecology, Evolution, and Behavior University of Minnesota Saint Paul Minnesota 55108
| | - Jessica L. Ward
- Department of Biology Ball State University Muncie Indiana 47306
| | - Ruth G. Shaw
- Department of Ecology, Evolution, and Behavior University of Minnesota Saint Paul Minnesota 55108
| | - Mark A. Bee
- Department of Ecology, Evolution, and Behavior University of Minnesota Saint Paul Minnesota 55108
- Graduate Program in Neuroscience University of Minnesota Minneapolis Minnesota 55455
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Sasson DA, Brockmann HJ. Geographic variation in sperm and ejaculate quantity and quality of horseshoe crabs. Behav Ecol Sociobiol 2016. [DOI: 10.1007/s00265-016-2177-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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10
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Funch P, Wang T, Pertoldi C, Middelbo AB. Low Oxygen Levels Slow Embryonic Development of Limulus polyphemus. THE BIOLOGICAL BULLETIN 2016; 231:113-119. [PMID: 27820903 DOI: 10.1086/690091] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The American horseshoe crab Limulus polyphemus typically spawns in the upper intertidal zone, where the developing embryos are exposed to large variations in abiotic factors such as temperature, humidity, salinity, and oxygen, which affect the rate of development. It has been shown that embryonic development is slowed at both high and low salinities and temperatures, and that late embryos close to hatching tolerate periodic hypoxia. In this study we investigated the influence of hypoxia on both early and late embryonic development in L. polyphemus under controlled laboratory conditions. Embryos were exposed to four different oxygen levels and their developmental stage was scored every second day. Embryos developed more slowly at both 5% O2 and 10% O2 than at the 21% O2 treatment; late development was arrested when oxygen was reduced to 2%. Our study confims that L. polyphemus not only tolerates pronounced hypoxia in later embryonic developmental stages, but also in earlier, previously unexplored, developmental stages.
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11
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Reproductive tactics and mating contexts affect sperm traits in horseshoe crabs (Limulus polyphemus). Behav Ecol Sociobiol 2015. [DOI: 10.1007/s00265-015-1989-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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12
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Smith MD, Brockmann HJ. The evolution and maintenance of sexual size dimorphism in horseshoe crabs: an evaluation of six functional hypotheses. Anim Behav 2014. [DOI: 10.1016/j.anbehav.2014.08.005] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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13
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Johnson SL, Brockmann HJ. Parental effects on early development: testing for indirect benefits of polyandry. Behav Ecol 2013. [DOI: 10.1093/beheco/art056] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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15
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Sasson DA, Johnson SL, Brockmann HJ. The role of age on sperm traits in the American horseshoe crab, Limulus polyphemus. Anim Behav 2012. [DOI: 10.1016/j.anbehav.2012.07.023] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
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17
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Johnson SL, Brockmann HJ. Alternative reproductive tactics in female horseshoe crabs. Behav Ecol 2012. [DOI: 10.1093/beheco/ars063] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Zaleha K, Kamaruzzam B, John BA, Ong M. Cd, Cu and Pb Concentration Levels in Horseshoe Crab Nesting Grounds of Pahang Coast, Malaysia. ACTA ACUST UNITED AC 2010. [DOI: 10.3923/jbs.2010.790.794] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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19
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20
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Kamel SJ, Grosberg RK, Marshall DJ. Family conflicts in the sea. Trends Ecol Evol 2010; 25:442-9. [DOI: 10.1016/j.tree.2010.05.008] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2010] [Revised: 05/21/2010] [Accepted: 05/25/2010] [Indexed: 10/19/2022]
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21
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Sato T, Harada Y. Synchronous female spawning and male mating behavior in a land-locked population of Japanese charr, Salvelinus leucomaenis japonicus. Zoolog Sci 2008; 25:766-72. [PMID: 18828665 DOI: 10.2108/zsj.25.766] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2007] [Accepted: 04/27/2008] [Indexed: 11/17/2022]
Abstract
In resource-based promiscuous mating systems, synchronous spawning of females affects competition among males and variation in the reproductive success of males. We documented the mating behavior of Japanese charr (Salvelinus leucomaenis japonicus) through an annual breeding season to examine the relationship between female spawning synchrony and male mating behavior. Females spawned highly synchronously in the population studied, i.e., approximately half the spawning was finished within the first three days of the entire spawning season (11 days). The daily operational sex ratio (OSR) was nearly 1:1 through the spawning period. The number of males around a spawning female was very small (1.21+/-0.49 males per female) over the spawning ground and period, suggesting that a competitive male could effectively chase subordinate males away from a spawning female. A few males attempted to sneak near the oviposition site of females (16%; 9 of 57 breeding groups), while some males adopted sneaking tactics in the initial phase of females' spawning (24%). We did not observe any males to succeed in sneak fertilizations. We conclude that in this Japanese charr population, the synchronous spawning of females was related to the unbiased daily OSR, male aggregation around females, and consequently whether and how efficiently males engaged in sneak mating behavior.
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Affiliation(s)
- Takuya Sato
- Laboratory of Fish Population Dynamics, Department of Bioresources, Graduate School of Mie University, Tsu, Mie, Japan.
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22
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Johnson SL, Yund PO. Variation in multiple paternity in natural populations of a free-spawning marine invertebrate. Mol Ecol 2007; 16:3253-62. [PMID: 17651201 DOI: 10.1111/j.1365-294x.2007.03366.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
For free-spawning marine invertebrates, fertilization processes control the genetic diversity of offspring. Each egg can potentially be fertilized by a sperm from a different male, and hence genetic diversity within a brood varies with levels of multiple paternity. Yet, few studies have characterized the frequency of multiple paternity in natural spawns. We analysed patterns of multiple paternity in two populations of the colonial ascidian Botryllus schlosseri using microsatellites. Because previous studies have shown that at moderate to high population densities, competition among male-phase B. schlosseri colonies results in the nearest male dominating the paternity of a brood, we specifically tested the effect of population density on patterns of paternity. Paternity was estimated using three multilocus indices: minimum number of fathers, counts of sperm haplotypes, and effective paternity (K(E)). Multiple paternity was evident in more than 92% of the broods analysed, but highly variable, with a few broods displaying unequal contributions of different males. We found no effect of population density on multiple paternity, suggesting that other factors may control paternity levels. Indirect benefits from increasing the genetic diversity of broods are a possible explanation for the high level of multiple paternity in this species.
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Affiliation(s)
- Sheri L Johnson
- Darling Marine Center, University of Maine, 193 Clarks Cove Road, Walpole, ME 04573, USA.
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23
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Duffy EE, Penn DJ, Botton ML, Brockmann HJ, Loveland RE. Eye and clasper damage influence male mating tactics in the horseshoe crab, Limulus polyphemus. J ETHOL 2005. [DOI: 10.1007/s10164-005-0163-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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24
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Wada T, Takegaki T, Mori T, Natsukari Y. Alternative Male Mating Behaviors Dependent on Relative Body Size in Captive Oval Squid Sepioteuthis lessoniana (Cephalopoda, Loliginidae). Zoolog Sci 2005; 22:645-51. [PMID: 15988158 DOI: 10.2108/zsj.22.645] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
We observed the reproductive behavior of the oval squid Sepioteuthis lessoniana in captivity. The male used three different mating behaviors: male-parallel (MP), male-upturned (MU) and sneaking. Male competition over females frequently occurred before and during the female egg-laying period, and the outcome of most fights depended on male body size. Larger males guarded their partners from other males and performed MP mating during the egg-laying period of the paired females. In contrast, there was no pairing and mate guarding in MU mating and sneaking, which were adopted by smaller subordinate males as alternative tactics outside female egg-laying period and during the period, respectively. MP matings were 95% successful, but more than half of MU matings were unsuccessful. Higher mating success in MP mating was achieved through pairing, whereas males in MU mating were less successful because mating attempts without pair formation were often foiled by escape of the female. Sneaking was successful in all cases but occurred less frequently. Spermatophores were attached at the opening of the oviduct in MP mating, whereas they were attached around the female buccal membrane in MU mating and sneaking. Considering the route of egg transportation, higher fertilization success can be expected in MP mating because of the advantageous location of the attached spermatophores. Our results suggest that MP mating is used by larger, paired males during the female egg-laying period, and that MU mating and sneaking are alternative tactics adopted by smaller, subordinate males. These alternative mating behaviors would be conditional strategy dependent on relative body size, because some individual males displayed both MP and MU mating behaviors.
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Affiliation(s)
- Toshifumi Wada
- Graduate School of Science and Technology, Nagasaki University, Fuluoka, Japan.
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25
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Walker D, Power AJ, Avise JC. Sex-linked Markers Facilitate Genetic Parentage Analyses in Knobbed Whelk Broods. J Hered 2004; 96:108-13. [PMID: 15618306 DOI: 10.1093/jhered/esi016] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
To explore the potential of sex-linked polymorphisms for genetic parentage analyses in natural populations, we have employed a recently discovered "X-linked" microsatellite marker (in conjunction with polymorphic autosomal loci) to deduce biological paternity and maternity for large numbers of encapsulated embryos within individual broods of the knobbed whelk (Busycon carica). Empirical findings illustrate how such sex-linked genetic tags can in special instances find at least three novel utilities in genetic dissections of large-clutch species: clarification of paternity assignments that had remained ambiguous from di-locus autosomal data alone; elucidation of linkage relationships among pairs of autosomal loci; and illumination of maternity (and thereby paternity also) in broods for which neither biological parent was known from independent evidence.
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Affiliation(s)
- D Walker
- Department of Genetics, University of Georgia, Athens, GA 30602, USA.
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26
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Naud MJ, Hanlon RT, Hall KC, Shaw PW, Havenhand JN. Behavioural and genetic assessment of reproductive success in a spawning aggregation of the Australian giant cuttlefish, Sepia apama. Anim Behav 2004. [DOI: 10.1016/j.anbehav.2003.10.005] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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27
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Walker D, Porter BA, Avise JC. Genetic parentage assessment in the crayfish Orconectes placidus, a high-fecundity invertebrate with extended maternal brood care. Mol Ecol 2002; 11:2115-22. [PMID: 12296953 DOI: 10.1046/j.1365-294x.2002.01609.x] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Microsatellite data have recently been introduced in the context of genetic maternity and paternity assignments in high-fecundity fish species with single-parent-tended broods. Here we extend such analyses to an aquatic invertebrate, the crayfish Orconectes placidus, in which gravid females carry large numbers of offspring. Genetic parentage analyses of more than 900 progeny from 15 wild crayfish broods revealed that gravid females were invariably the exclusive dams of the offspring they tended (i.e. there was no allomaternal care), and that most of the females had mated with multiple (usually two) males who contributed sometimes highly skewed numbers of offspring to a brood. Within any multiply sired brood, the unhatched eggs (or the hatched juveniles) from different fathers were randomly distributed across the mother's brood space. All of these genetic findings are discussed in the light of observations on the mating behaviours and reproductive biology of crayfish.
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Affiliation(s)
- D Walker
- Department of Genetics, University of Georgia, Athens, GA 30602, USA.
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28
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Hassler C, Brockmann HJ. Evidence for use of chemical cues by male horseshoe crabs when locating nesting females (Limulus polyphemus). J Chem Ecol 2001; 27:2319-35. [PMID: 11817084 DOI: 10.1023/a:1012291206831] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Horseshoe crabs come ashore in attached pairs during spring high tides to mate and nest on beaches of the Atlantic and Gulf coasts. Unattached males also come ashore and crowd around the nesting pairs as satellites and engage in sperm competition with the attached male. Females with no satellites and females with large numbers of satellites nest next to one another on the same tide. When females are removed and replaced by a cement model, satellite males continue to be attracted to the same location. Models over sites where females with many satellites had nested are more attractive to males than sites from which a female with no satellites had been removed or a site where no crab had been nesting recently. A second experiment demonstrated that males are responding to chemical cues. A sponge filled with seawater taken from below a female with many satellites and placed under a model female was more attractive to males than a sponge filled with seawater. This is the first demonstration that horseshoe crabs use chemical cues, in addition to visual cues, to locate mates.
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Affiliation(s)
- C Hassler
- Department of Zoology, University of Florida, Gainesville 32611-8525, USA
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29
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Brockmann HJ. The evolution of alternative strategies and tactics. ADVANCES IN THE STUDY OF BEHAVIOR 2001. [DOI: 10.1016/s0065-3454(01)80004-8] [Citation(s) in RCA: 193] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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