Editing Poison dart frog (section)

=== Other factors ===
[[Dietary conservatism]] (long-term [[neophobia]]) in predators could facilitate the evolution of warning coloration, if predators avoid novel morphs for a long enough period of time.<ref>{{cite journal |last1=Marples |first1=N. M. |year=2005 |title=Perspective: The evolution of warning coloration is not paradoxical |journal=Evolution |volume=59 |pages=933–940 |pmid=16136793 |last2=Kelly |first2=D. J. |last3=Thomas |first3=R. J. |issue=5 |doi=10.1111/j.0014-3820.2005.tb01032.x |s2cid=24118222 |doi-access=free }}</ref> Another possibility is genetic drift, the so-called gradual-change hypothesis, which could strengthen weak pre-existing aposematism.<ref>{{cite journal |last1=Lindström |first1=L. |year=1999 |title=Can aposematic signals evolve by gradual change? |url=http://users.jyu.fi/~lilema/papers_files/1999_Nature.pdf|journal=Nature |volume=397 |pages=249–251 |doi=10.1038/16692 |last2=Alatalo |first2=Rauno V. |last3=Mappes |first3=Johanna |last4=Riipi |first4=Marianna |last5=Vertainen |first5=Laura |issue=6716|bibcode=1999Natur.397..249L |s2cid=4330762 }}</ref>

Sexual selection may have played a role in the diversification of skin color and pattern in poison frogs.<ref>{{cite journal|last=Mann |first=M.E. |author2=Cummings, M. E. |title=Sexual dimorphism and directional sexual selection on aposematic signals in a poison frog |journal=PNAS |year=2009 |issue=45 |pages=19072–19077 |doi=10.1073/pnas.0903327106 |volume=106 |pmid=19858491 |pmc=2776464 |bibcode=2009PNAS..10619072M |doi-access=free }}</ref><ref>{{cite journal |last=Summers |first=K. |author2=L. Bermingham |author3=S. Weigt |author4=S. McCafferty |author5=L. Dahlstrom |title=Phenotypic and genetic divergence in three species of dart-poison frogs with contrasting parental behavior |journal=The Journal of Heredity |year=1997 |volume=88 |issue=1 |pages=8–13 |pmid=9048443 |doi=10.1093/oxfordjournals.jhered.a023065|doi-access=free }}</ref><ref>{{cite journal|last=Rudh |first=A. |author2=B. Rogell |author3=J. Hoglund|title=Non-gradual variation in color morphs of the strawberry poison frog Dendrobates pumilio: genetic and geographical isolation suggest a role for selection in maintaining polymorphism |journal=Molecular Ecology |year=2007 |volume=16 |issue=20 |pages=4282–4294 |pmid=17868297 |doi=10.1111/j.1365-294X.2007.03479.x|s2cid=41814698 }}</ref><ref>{{cite journal|last=Maan |first=M. E. |author2=M. E. Cummings |title=Sexual dimorphism and directional selection on aposematic signals in a poison frog |journal=PNAS |year=2009 |volume=106|issue=45 |pages=19072–19077 |doi=10.1073/pnas.0903327106 |pmid=19858491 |pmc=2776464|bibcode=2009PNAS..10619072M |doi-access=free }}</ref> With female preferences in play, male coloration could evolve rapidly. Sexual selection is influenced by many things. The parental investment may shed some light on the evolution of coloration in relation to female choice. In ''[[Oophaga pumilio]]'', the female provides care for the offspring for several weeks whereas the males provides care for a few days, implying a strong female preference. Sexual selection increases phenotypic variation drastically. In populations of ''O. pumilio'' that participated in sexual selection, the phenotypic polymorphism was evident.<ref>{{cite journal |last=Tazzyman |first=S.J. |author2=Iwasa, Y. |title=Sexual selection can increase the effect of random genetic drift-a quantitative genetic model of polymorphism in oophaga pumilio, the strawberry poison-dart frog |journal=Evolution |year=2010 |issue=6 |pages=1719–1728 |doi=10.1111/j.1558-5646.2009.00923.x |volume=64 |pmid=20015236|s2cid=37757687 |doi-access= }}</ref> The lack of [[sexual dimorphism]] in some dendrobatid populations however suggests that sexual selection is not a valid explanation.<ref>{{cite journal |last=Rudh |first=Andreas |author2=B. Rogell |author3=O. Håstad |author4=A. Qvarnström |title=Rapid population divergence linked with co-variation between coloration and sexual display in strawberry poison frogs |journal=Evolution |year=2011 |issue=5 |pages=1271–1282 |doi=10.1111/j.1558-5646.2010.01210.x |volume=65 |pmid=21166789|s2cid=10785432 }}</ref>

Functional trade-offs are seen in poison frog defense mechanisms relating to toxin resistance. Poison dart frogs containing epibatidine have undergone a 3 amino acid mutation on receptors of the body, allowing the frog to be resistant to its own poison. Epibatidine-producing frogs have evolved poison resistance of body receptors independently three times. This target-site insensitivity to the potent toxin epibatidine on nicotinic acetylcholine receptors provides a toxin resistance while reducing the affinity of acetylcholine binding.<ref>{{Cite journal |last1=Tarvin |first1=Rebecca D. |last2=Borghese |first2=Cecilia M. |last3=Sachs |first3=Wiebke |last4=Santos |first4=Juan C. |last5=Lu |first5=Ying |last6=O'Connell |first6=Lauren A. |author-link6=Lauren O'Connell (scientist) |last7=Cannatella |first7=David C. |last8=Harris |first8=R. Adron |last9=Zakon |first9=Harold H. |date=2017-09-22 |title=Interacting amino acid replacements allow poison frogs to evolve epibatidine resistance |journal=Science |volume=357 |issue=6357 |pages=1261–1266 |bibcode=2017Sci...357.1261T |doi=10.1126/science.aan5061 |issn=0036-8075 |pmc=5834227 |pmid=28935799}}</ref>