# Reduced conspicuousness evolves with increased toxicity.



## Zhuisky45 (Feb 17, 2014)

Interesting research article on the relationship between toxicity and conspicuousness (Bright colors) in the species D. granuliferus. Not what you may have thought. Not sure if this holds true for all species. (Phyllobates terribilis "Orange")

http://nature.berkeley.edu/wanglab/papers/Wang2011Evolution.pdf


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## rmp (Oct 28, 2015)

It is interesting indeed. The correlation between conspicuousness and toxicity can happen in two ways: First consider that aposematic animals have bright colors to advertise their defenses, and that predators will learn to associate the signals with the defenses and avoid them after a couple of bad experiences. Therefore, if a much brighter signal will be much easier to remember, and may not need to have as much toxin to cause a strong impression on the naive predators that try to eat the frog. In this case you would get what Wang finds in granulifera. On the other hand, if you are putting a lot of energy into making a lot of toxin it makes sense to be very conspicuous so that the whole strategy works really well, as seems to happen in Phyllobates (although some populations of aurotaenia can be very very toxic, probably as much as bicolor). In the end, I think it depends on what predators are involved, how they see color, how well they learn, how tolerant they are to toxins, etc...


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## froggorf (Nov 22, 2008)

I think rmp brings up some really good points and if this topic of toxicity in dart frogs interests you, check out Maan and Cummings 2012 in American Naturalist on pumilio coloration as honest signals to avian predators.


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## Zhuisky45 (Feb 17, 2014)

Very good summary RMP. Predication may vary in regions as well as toxin availability. Not sure if it was this article or different one that touched on that. However, different factors need to be considered but typically the two consideration you made hold true. Thanks also froggorf for the referenced article.


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## rmp (Oct 28, 2015)

froggorf said:


> I think rmp brings up some really good points and if this topic of toxicity in dart frogs interests you, check out Maan and Cummings 2012 in American Naturalist on pumilio coloration as honest signals to avian predators.


Also see Summer's et al 2015 review on the honesty of aposematic signals on the Journal of Evol Biol (Are aposematic signals honest? A review - Summers - 2015 - Journal of Evolutionary Biology - Wiley Online Library). If you want the pdf but hit a paywall send me a pm.


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## Ed (Sep 19, 2004)

This has to be contrasted with some other studies specifically 

Saporito, Ralph A., et al. "Spatial and temporal patterns of alkaloid variation in the poison frog Oophaga pumilio in Costa Rica and Panama over 30 years." Toxicon 50.6 (2007): 757-778.

Saporito, Ralph A., et al. "Geographic and seasonal variation in alkaloid-based chemical defenses of Dendrobates pumilio from Bocas del Toro, Panama." Journal of chemical ecology 32.4 (2006): 795-814.

Saporito, Ralph A., et al. "Sex-Related Differences in Alkaloid Chemical Defenses of the Dendrobatid Frog Oophaga pumilio from Cayo Nancy, Bocas del Toro, Panama⊥." Journal of natural products 73.3 (2009): 317-321.

There is good data that shows large amounts of variation in the toxicity of animals within and between populations over both time and distance. 

Some comments 

Ed


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