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Wang Y, Hong X, Liu X, Li W, Chen C, Zhu J, Wei C, Zhu X, Yu L. Reproductive Output Reveals the Maternal Effects on Offspring Size-Number Trade-Off in Cultured Asian Yellow Pond Turtle ( Mauremys mutica). Animals (Basel) 2023; 13:2219. [PMID: 37444017 DOI: 10.3390/ani13132219] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2023] [Revised: 06/30/2023] [Accepted: 07/05/2023] [Indexed: 07/15/2023] Open
Abstract
Offspring size-number trade-off is a critical component of life-history theory and is important for further understanding the reproductive strategies of animals. The relationship between this trade-off and maternal size has been explored in several turtle species, except for the Asian yellow pond turtle, Mauremys mutica. To investigate how the maternal condition affects offspring size and number, we explored the relationships among the maternal body size and the number and size of cultured M. mutica hatchlings using a 4-year dataset. Our results showed that different females not only produced different sizes of offspring but also produced different numbers of offspring. No trade-off in egg size number was detected. According to regression analysis, we did not find that the maternal body size significantly influenced the offspring mass; however, we detected that the offspring size was significantly correlated with the clutch size and maternal age. The mean body mass of offspring increased with maternal age, and the clutch size varied significantly over four years, which was correlated with offspring size, maternal body size and age. However, the number of offspring per female increased with the maternal plastron length rather than age. Our results were inconsistent with the optimal offspring size theory in that females did not increase their offspring size but rather increased the offspring number to increase their fitness, which will also provide a basis for the efficient cultivation management of turtles.
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Affiliation(s)
- Yakun Wang
- Key Laboratory of Tropical & Subtropical Fishery Resource Application & Cultivation of Ministry of Agriculture and Rural Affairs, Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou 510380, China
| | - Xiaoyou Hong
- Key Laboratory of Tropical & Subtropical Fishery Resource Application & Cultivation of Ministry of Agriculture and Rural Affairs, Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou 510380, China
| | - Xiaoli Liu
- Key Laboratory of Tropical & Subtropical Fishery Resource Application & Cultivation of Ministry of Agriculture and Rural Affairs, Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou 510380, China
| | - Wei Li
- Key Laboratory of Tropical & Subtropical Fishery Resource Application & Cultivation of Ministry of Agriculture and Rural Affairs, Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou 510380, China
| | - Chen Chen
- Key Laboratory of Tropical & Subtropical Fishery Resource Application & Cultivation of Ministry of Agriculture and Rural Affairs, Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou 510380, China
| | - Junxian Zhu
- Key Laboratory of Tropical & Subtropical Fishery Resource Application & Cultivation of Ministry of Agriculture and Rural Affairs, Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou 510380, China
| | - Chengqing Wei
- Key Laboratory of Tropical & Subtropical Fishery Resource Application & Cultivation of Ministry of Agriculture and Rural Affairs, Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou 510380, China
| | - Xinping Zhu
- Key Laboratory of Tropical & Subtropical Fishery Resource Application & Cultivation of Ministry of Agriculture and Rural Affairs, Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou 510380, China
| | - Lingyun Yu
- Key Laboratory of Tropical & Subtropical Fishery Resource Application & Cultivation of Ministry of Agriculture and Rural Affairs, Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou 510380, China
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Yu W, Zhu Z, Zhao X, Cui S, Liu Z, Zeng Z. Altitudinal variation in life-history features of a Qinghai-Tibetan Plateau lizard. Curr Zool 2023; 69:284-293. [PMID: 37351291 PMCID: PMC10284057 DOI: 10.1093/cz/zoac052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Revised: 06/17/2022] [Accepted: 06/30/2022] [Indexed: 09/18/2023] Open
Abstract
Environmental changes along an altitudinal gradient can facilitate the differentiation of life-history features in ectothermic species, but little attention has been devoted to the reciprocal influence of altitude and alpine slope directionality on life-history variation. According to life-history theory, increased environmental stress causes a change in reproductive allocation from number to quality of offspring, as well as a stronger trade-off between size and number of offspring. To clarify the influence of environmental pressures on the life-history features of the Qinghai toad-headed lizard Phrynocephalus vlangalii along an altitudinal cline, we surveyed late pregnant females from 3 populations of low (2,600 m), middle (3,400 m), and high (3,600 m) elevations in the Dangjin Mountain of Gansu, China from July to October 2019, and compared their inter-population differences in maternal body size, reproductive characteristics, offspring growth, and locomotor performance. Because of lower temperatures, higher humidity, and lower light intensity caused by slope aspect and altitude, the middle-altitude region experienced stronger environmental stress than the high- and low-altitude regions. Our results showed that females were larger at middle- and high-altitude sites and smaller at the low-altitude site, following Bergmann's rule. We also found that females from low-altitude population gave birth earlier than those from the middle and high altitudes. Our results showed a shift in the offspring size-number trade-off of P. vlangalii in response to colder and harsher environments, with lizards from the alpine steppe (i.e. the middle- and high-altitude habitats) producing fewer but larger offspring than those from the warm steppe (i.e. the low-altitude habitat). Low-altitude juveniles grew faster than high-altitude ones, but at the same rates as middle-altitude juveniles. This result demonstrates that the growth of P. vlangalii was associated with temperature and light intensity. Our findings contribute to enhancing our understanding of the altitudinal variation in life-history features of plateau ectotherms and their phenotypic plasticity or local adaptation.
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Affiliation(s)
- Wei Yu
- College of Wildlife Resources, Northeast Forestry University, Harbin 150040, China
- Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China
| | - Zeyu Zhu
- College of Wildlife Resources, Northeast Forestry University, Harbin 150040, China
- Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China
| | - Xiaolong Zhao
- Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China
- The Key Laboratory of Zoological Systematics and Application, School of Life Science, Institute of Life Science and Green Development, Hebei University, Baoding 071002, Hebei, China
| | - Shuang Cui
- College of Wildlife Resources, Northeast Forestry University, Harbin 150040, China
| | - Zhensheng Liu
- College of Wildlife Resources, Northeast Forestry University, Harbin 150040, China
- Key Laboratory of Conservation Biology, State Forestry Administration, Harbin 150040, China
| | - Zhigao Zeng
- Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China
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3
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Barateli N, Tarkhnishvili D, Iankoshvili G, Kokiashvili L. Reproductive effort of unisexual and bisexual rock lizards (genus Darevskia). ZOOL ANZ 2022. [DOI: 10.1016/j.jcz.2022.11.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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4
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Toupin LP, Ratz T, Montiglio PO. Effects of resource availability on the web structure of female western black widows: is the web structure constrained by physiological trade-offs? Behav Ecol 2022. [DOI: 10.1093/beheco/arac086] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
A major challenge of biological research is to understand what generates and maintains consistent behavioral variation among animals. Time and energy trade-offs, where expressing one behavior is achieved at the expense of another, are often suggested to favor the maintenance of behavioral differences between individuals. However, few studies have investigated how individuals adjust their allocation to different functions over time and depending on resource abundance. Black widow spiders of the genus Latrodectus build persistent webs that include structural threads which protect against predators and sticky trap threads to capture prey. Web structure consistently differs among individuals in the number of trap and structural threads. To quantify the intensity of a trade-off, we assessed the relationship between the number of structural and trap threads and tested whether varying food abundance affected individual differences in web structure. We further quantified how these individual differences change over time and with food abundance. We subjected spiders to three different levels of prey abundance and monitored the structure of their webs every twelve hours. We found no evidence for a trade-off between trap and structural threads. Instead, spiders that produced more structural threads also produced more trap threads, showing that spiders invested equally in both types of threads. Interestingly, the magnitude of individual differences in web structure was greatest when spiders were fed ad libitum and at the beginning of web construction. We suggest that variation in web structure between spiders could be the result of stable developmental differences in morphology or genetic differences.
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Affiliation(s)
- Louis-Philippe Toupin
- Département des Sciences Biologiques, Université du Québec à Montréal , CP-8888 Succursale Centre-ville, Montréal, QC, H3C 3P , Canada
| | - Tom Ratz
- Département des Sciences Biologiques, Université du Québec à Montréal , CP-8888 Succursale Centre-ville, Montréal, QC, H3C 3P , Canada
- Behavioural Ecology, Department of Biology, Ludwig-Maximilians University of Munich (LMU) , Planegg-Martinsried , Germany
| | - Pierre-Olivier Montiglio
- Département des Sciences Biologiques, Université du Québec à Montréal , CP-8888 Succursale Centre-ville, Montréal, QC, H3C 3P , Canada
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Ljubisavljević K, Anđelković M, Urošević A, Roitberg ES. Female reproductive characteristics of the Balkan sand lizard Lacerta agilis bosnica (Schreiber, 1912). REV SUISSE ZOOL 2022. [DOI: 10.35929/rsz.0069] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Affiliation(s)
- Katarina Ljubisavljević
- University of Belgrade, Institute for Biological Research “Siniša Stanković” - National Institute of the Republic of Serbia, Department of Evolutionary Biology, Bulevar Despota Stefana 142, 11060 Belgrade, Serbia
| | - Marko Anđelković
- University of Belgrade, Institute for Biological Research “Siniša Stanković” - National Institute of the Republic of Serbia, Department of Evolutionary Biology, Bulevar Despota Stefana 142, 11060 Belgrade, Serbia
| | - Aleksandar Urošević
- University of Belgrade, Institute for Biological Research “Siniša Stanković” - National Institute of the Republic of Serbia, Department of Evolutionary Biology, Bulevar Despota Stefana 142, 11060 Belgrade, Serbia
| | - Evgeny S. Roitberg
- Zoological Research Museum Alexander Koenig, Adenauerallee 160, 53113 Bonn, Germany
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Caracalas HE, French SS, Hudson SB, Kluever BM, Webb AC, Eifler D, Lehmicke AJ, Aubry LM. Reproductive trade-offs in the colorado checkered whiptail lizard (Aspidoscelis neotesselatus): an examination of the relationship between clutch and follicle size. Evol Ecol 2021. [DOI: 10.1007/s10682-021-10131-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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7
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Olsson M, Schwartz TS, Wapstra E, Shine R. How accurately do behavioural observations predict reproductive success in free-ranging lizards? Biol Lett 2019; 15:20190030. [PMID: 30958138 PMCID: PMC6405472 DOI: 10.1098/rsbl.2019.0030] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2019] [Accepted: 01/29/2019] [Indexed: 11/12/2022] Open
Abstract
Behavioural ecologists often use data on patterns of male-female association to infer reproductive success of free-ranging animals. For example, a male seen with several females during the mating season is predicted to father more offspring than a male not seen with any females. We explored the putative correlation between this behaviour and actual paternity (as revealed by microsatellite data) from a long-term study on sand lizards ( Lacerta agilis), including behavioural observations of 574 adult males and 289 adult females, and paternity assignment of more than 2500 offspring during 1998-2007. The number of males that contributed paternity to a female's clutch was correlated with the number of males seen accompanying her in the field, but not with the number of copulation scars on her body. The number of females that a male accompanied in the field predicted the number of females with whom he fathered offspring, and his annual reproductive success (number of progeny). Although behavioural data explained less than one-third of total variance in reproductive success, our analysis supports the utility of behavioural-ecology studies for predicting paternity in free-ranging reptiles.
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Affiliation(s)
- Mats Olsson
- Department of Biological and Environmental Sciences, University of Gothenburg, Medicinaregatan 18, 413-90 Gothenburg, Sweden
| | - Tonia S. Schwartz
- Department of Biological Sciences, Auburn University, Auburn, AL 36849, USA
| | - Erik Wapstra
- School of Biological Sciences, University of Tasmania, Private Bag 55, Hobart 7001, Australia
| | - Richard Shine
- School of Life and Environmental Sciences, University of Sydney, Sydney, New South Wales 2006, Australia
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8
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Abreu LRA, Ribeiro VMP, Gouveia GC, Cardoso EP, Toral FLB. Genetic trends and trade-offs between growth and reproductive traits in a Nellore herd. PLoS One 2018; 13:e0201392. [PMID: 30114191 PMCID: PMC6095503 DOI: 10.1371/journal.pone.0201392] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Accepted: 07/13/2018] [Indexed: 11/19/2022] Open
Abstract
The knowledge of genetic trends and trade-offs between growth and reproductive traits might be useful to understand the evolution of these traits in livestock and natural populations of animals. We estimated the genetic trends and trade-offs between pre-weaning growth and calving intervals of Nellore animals from a commercial farm. Two-trait animal models were used to estimate covariance components and breeding values (EBV) for direct and maternal genetic effects of pre-weaning growth and direct genetic effects of calving intervals. Regression analyses were performed to examine the relationship between direct and maternal EBV of pre-weaning growth and direct EBV of calving intervals (dependent variables) and the coefficient of generation of each animal (independent variable). We also performed regression analyses to examine the relationship between direct EBV of calving intervals (dependent variables) and direct and maternal EBV of pre-weaning growth (independent variables). The genetic trends for direct and maternal genetic effect for pre-weaning growth were significant and presented genetic evolution in the studied Nellore herd. The genetic trends for the reproductive traits were also significant but indicated genetic changes in an unfavorable way. The genetic correlations between direct effects of pre-weaning growth and calving intervals traits and the genetic correlations between maternal effects of pre-weaning growth traits and direct effects of calving interval traits were not different from zero. The presence of trade-offs between the direct effects of growth and reproductive traits were confirmed through regression from direct EBV of calving intervals over EBV of pre-weaning growth traits. In addition, regression analyses showed that selection to increase pre-weaning growth also increased calving intervals. Our results showed that pre-weaning growth and calving intervals are increasing over generations and that trade-offs occurred between those traits in the studied Nellore herd.
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Affiliation(s)
- Luiza Rodrigues Alves Abreu
- Departamento de Zootecnia, Escola de Veterinária, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
| | | | - Gabriela Canabrava Gouveia
- Departamento de Zootecnia, Escola de Veterinária, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
| | | | - Fabio Luiz Buranelo Toral
- Departamento de Zootecnia, Escola de Veterinária, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
- * E-mail:
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9
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Ramakers JJC, Culina A, Visser ME, Gienapp P. Environmental coupling of heritability and selection is rare and of minor evolutionary significance in wild populations. Nat Ecol Evol 2018; 2:1093-1103. [PMID: 29915341 PMCID: PMC6027994 DOI: 10.1038/s41559-018-0577-4] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Accepted: 05/15/2018] [Indexed: 01/01/2023]
Abstract
Predicting the rate of adaptation to environmental change in wild populations is important for understanding evolutionary change. However, predictions may be unreliable if the two key variables affecting the rate of evolutionary change-heritability and selection-are both affected by the same environmental variable. To determine how general such an environmentally induced coupling of heritability and selection is, and how this may influence the rate of adaptation, we made use of freely accessible, open data on pedigreed wild populations to answer this question at the broadest possible scale. Using 16 populations from 10 vertebrate species, which provided data on 50 traits (relating to body mass, morphology, physiology, behaviour and life history), we found evidence for an environmentally induced relationship between heritability and selection in only 6 cases, with weak evidence that this resulted in an increase or decrease in the expected selection response. We conclude that such a coupling of heritability and selection is unlikely to strongly affect evolutionary change, even though both heritability and selection are commonly postulated to be dependent on the environment.
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Affiliation(s)
- Jip J C Ramakers
- Department of Animal Ecology, Netherlands Institute of Ecology, Wageningen, the Netherlands.
| | - Antica Culina
- Department of Animal Ecology, Netherlands Institute of Ecology, Wageningen, the Netherlands
| | - Marcel E Visser
- Department of Animal Ecology, Netherlands Institute of Ecology, Wageningen, the Netherlands
| | - Phillip Gienapp
- Department of Animal Ecology, Netherlands Institute of Ecology, Wageningen, the Netherlands
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10
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Olsson M, Loeb L, Lindsay W, Wapstra E, Fitzpatrick L, Shine R. Extreme plasticity in reproductive biology of an oviparous lizard. Ecol Evol 2018; 8:6384-6389. [PMID: 30038742 PMCID: PMC6053574 DOI: 10.1002/ece3.4247] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2018] [Revised: 04/30/2018] [Accepted: 05/03/2018] [Indexed: 12/04/2022] Open
Abstract
Most oviparous squamate reptiles lay their eggs when embryos have completed less than one-third of development, with the remaining two-thirds spent in an external nest. Even when females facultatively retain eggs in dry or cold conditions, such retention generally causes only a minor (<10%) decrease in subsequent incubation periods. In contrast, we found that female sand lizards (Lacerta agilis) from an experimentally founded field population (established ca. 20 years ago on the southwest coast of Sweden) exhibited wide variation in incubation periods even when the eggs were kept at standard (25°C) conditions. Females that retained eggs in utero for longer based on the delay between capture and oviposition produced eggs that hatched sooner. In the extreme case, eggs hatched after only 55% of the "normal" incubation period. Although the proximate mechanisms underlying this flexibility remain unclear, our results from this first full field season at the new study site show that females within a single cold-climate population of lizards can span a substantial proportion of the continuum from "normal" oviparity to viviparity.
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Affiliation(s)
- Mats Olsson
- Division of Animal EcologyDepartment of ZoologyUniversity of GothenburgGothenburgSweden
- School of Biological SciencesUniversity of WollongongWollongongNSWAustralia
| | - Lisa Loeb
- Division of Animal EcologyDepartment of ZoologyUniversity of GothenburgGothenburgSweden
| | - Willow Lindsay
- Division of Animal EcologyDepartment of ZoologyUniversity of GothenburgGothenburgSweden
| | - Erik Wapstra
- School of Biological SciencesUniversity of TasmaniaHobartTasmaniaAustralia
| | - Luisa Fitzpatrick
- School of Biological SciencesUniversity of TasmaniaHobartTasmaniaAustralia
| | - Richard Shine
- School of Life and Environmental SciencesUniversity of SydneySydneyNSWAustralia
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11
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Shine R, Wapstra E, Olsson M. Seasonal shifts along the oviparity–viviparity continuum in a cold‐climate lizard population. J Evol Biol 2017; 31:4-13. [DOI: 10.1111/jeb.13202] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2017] [Accepted: 10/22/2017] [Indexed: 11/29/2022]
Affiliation(s)
- R. Shine
- School of Life and Environmental Sciences University of Sydney Sydney NSW Australia
| | - E. Wapstra
- School of Biological Sciences University of Tasmania Hobart Tasmania Australia
| | - M. Olsson
- Department of Biological and Environmental Sciences University of Gothenburg Gothenburg Sweden
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12
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Egg Size Versus Number of Offspring Trade-Off: Female Age Rather Than Size Matters in a Domesticated Arctic Charr Population. Evol Biol 2017. [DOI: 10.1007/s11692-017-9433-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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13
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Ennen JR, Lovich JE, Averill-Murray RC, Yackulic CB, Agha M, Loughran C, Tennant L, Sinervo B. The evolution of different maternal investment strategies in two closely related desert vertebrates. Ecol Evol 2017; 7:3177-3189. [PMID: 28480017 PMCID: PMC5415531 DOI: 10.1002/ece3.2838] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2016] [Revised: 01/26/2017] [Accepted: 01/28/2017] [Indexed: 11/11/2022] Open
Abstract
We compared egg size phenotypes and tested several predictions from the optimal egg size (OES) and bet-hedging theories in two North American desert-dwelling sister tortoise taxa, Gopherus agassizii and G. morafkai, that inhabit different climate spaces: relatively unpredictable and more predictable climate spaces, respectively. Observed patterns in both species differed from the predictions of OES in several ways. Mean egg size increased with maternal body size in both species. Mean egg size was inversely related to clutch order in G. agassizii, a strategy more consistent with the within-generation hypothesis arising out of bet-hedging theory or a constraint in egg investment due to resource availability, and contrary to theories of density dependence, which posit that increasing hatchling competition from later season clutches should drive selection for larger eggs. We provide empirical evidence that one species, G. agassizii, employs a bet-hedging strategy that is a combination of two different bet-hedging hypotheses. Additionally, we found some evidence for G. morafkai employing a conservative bet-hedging strategy. (e.g., lack of intra- and interclutch variation in egg size relative to body size). Our novel adaptive hypothesis suggests the possibility that natural selection favors smaller offspring in late-season clutches because they experience a more benign environment or less energetically challenging environmental conditions (i.e., winter) than early clutch progeny, that emerge under harsher and more energetically challenging environmental conditions (i.e., summer). We also discuss alternative hypotheses of sexually antagonistic selection, which arise from the trade-offs of son versus daughter production that might have different optima depending on clutch order and variation in temperature-dependent sex determination (TSD) among clutches. Resolution of these hypotheses will require long-term data on fitness of sons versus daughters as a function of incubation environment, data as yet unavailable for any species with TSD.
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Affiliation(s)
- Joshua R Ennen
- Tennessee Aquarium Conservation Institute Chattanooga TN USA
| | - Jeffrey E Lovich
- U.S. Geological Survey Southwest Biological Science Center Flagstaff AZ USA
| | - Roy C Averill-Murray
- Nongame Branch Arizona Game and Fish Department Phoenix AZ USA.,Present address: Desert Tortoise Recovery Office United States Fish and Wildlife Service Reno NV 89502 USA
| | - Charles B Yackulic
- U.S. Geological Survey Southwest Biological Science Center Flagstaff AZ USA
| | - Mickey Agha
- Department of Wildlife, Fish, and Conservation Biology University of California, Davis Davis CA USA
| | - Caleb Loughran
- Department of Biology University of New Mexico Albuquerque NM USA
| | - Laura Tennant
- U.S. Geological Survey Southwest Biological Science Center Flagstaff AZ USA
| | - Barry Sinervo
- Department of Ecology and Evolutionary Biology University of California at Santa Cruz Santa Cruz CA USA
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