Surprisingly, little is known about body‐size evolution within the most diverse amphibian order, anurans (frogs and toads), despite known effects of body size on the physiological, ecological and life‐history traits of animals more generally. Here, we examined anuran body‐size evolution among 2,434 species with over 200 million years of shared evolutionary history. We found clade‐specific evolutionary shifts to new body‐size optima along with numerous independent transitions to gigantic and miniature body sizes, despite the upper limits of anuran body size remaining quite consistent throughout the fossil record. We found a weak, positive correlation between a species’ body size and maximum latitude and elevation, including a dearth of small species at higher elevations and broader latitudinal and elevational ranges in larger anurans. Although we found modest differences in mean anuran body size among microhabitats, there was extensive overlap in the range of body sizes across microhabitats. Finally, we found that larger anurans are more likely to consume vertebrate prey than smaller anurans are and that species with a free‐swimming larval phase during development are larger on average than those in which development into a froglet occurs within the egg. Overall, anuran body size does not conform to geographic and ecological patterns observed in other tetrapods but is perhaps more notable for variation in body size within geographic regions, ecologies and life histories. Here, we document this variation and propose target clades for detailed studies aimed at disentangling how and why variation in body size was generated and is maintained in anurans.
Across plants and animals, genome size is often correlated with life‐history traits: large genomes are correlated with larger seeds, slower development, larger body size and slower cell division. Among decapod crustaceans, caridean shrimps are among the most variable both in terms of genome size variation and life‐history characteristics such as larval development mode and egg size, but the extent to which these traits are associated in a phylogenetic context is largely unknown. In this study, we examine correlations among egg size, larval development and genome size in two different genera of snapping shrimp,
- Award ID(s):
- 1924675
- NSF-PAR ID:
- 10447368
- Publisher / Repository:
- Oxford University Press
- Date Published:
- Journal Name:
- Journal of Evolutionary Biology
- Volume:
- 34
- Issue:
- 11
- ISSN:
- 1010-061X
- Format(s):
- Medium: X Size: p. 1827-1839
- Size(s):
- ["p. 1827-1839"]
- Sponsoring Org:
- National Science Foundation
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Abstract Elucidating factors that limit the number of offspring produced is fundamental to understanding life‐history evolution. Here, we examine the hypothesis that parental ability to maintain an optimal physical developmental environment for all offspring constrains clutch size via effects on offspring quality.
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average incubation temperature among eggswithin nests increased with clutch size and exceeded 1°C in large clutches. Clutch size did not affect hatch success.In conjunction with our companion laboratory studies that used artificial incubation to document the effects of temperature variation on fitness‐related traits in this species, our work suggests that suboptimal incubation temperatures could be a factor that limits clutch size through diminishing returns on post‐hatch offspring quality.
A free
plain language summary can be found within the Supporting Information of this article. -
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