Camouflage – Why did it evolve in the first place?


Camouflage and mimicry are used by plants and animals alike throughout the natural world (Niu, Sun & Stevens 2018). It can help an organism hide in plain sight, mimic other more toxic creatures in self-defence or lure prey to a predator (Skelhorn & Rowe 2016).  Over the next few weeks we’ll explore these in more detail but today I would like to talk about the how and why of this fascinating and amazing thing.

So, how did camouflage evolve? Why did an organism suddenly need to hide from predators? And in some cases, why did predators need to outsmart their prey? I was recently introduced to the Light Switch Theory (Parker 2011) when I read an article for my Evolutionary Biology tutorial. Parker (2011), states that the first image-based eye was developed in the Cambrian period, about 521 MA. This has been found in fossils in Canada known as the Burgess fauna and flora. These fossils show each of the phyla that exist today, which there are 37 in total.

Before organisms developed the image-based eye, they had eyes that could distinguish light and dark. Meaning, the organisms knew where they were in relation to the sun, but not much else and relied on their other senses to find food or stay away from trouble (Parker 2011). Once the first predator developed the eye its prey had to evolve quickly to keep from being their next meal. This meant creating hard armoured bodies, bright warning colours and, you guessed it, camouflage to protect themselves.

I particularly like this quote from Parker (2003, p.42):

“The animal kingdom exploded into life, and the country of the blind became a teeming mass of hunters and hunted, all scrambling for their place on the evolutionary tree.”


For me, this sentence invokes the fight for survival, and in turn evolution, of the organisms that were alive in the Cambrian period. No wonder some organisms had to develop camouflage to survive! This is, of course, not the only theory for evolution but it is the one that I believe is most plausible.  



References

Parker, A 2003 ‘The Flick of a Sensory Switch’, Australasian Science, vol. 24, no.9, pp. 40-42.
Parker, A 2011 ‘On the Origin of Optics’, Optics & Laser Technology, vol. 43, pp. 323-329.
Niu, Y, Sun, H, & Stevens, M 2018 ‘Plant Camouflage: Ecology, Evolution, and Implications’, Trends in Ecology & Evolution, vol. 33, no. 8, pp. 608-618.
Skelhorn, J & Rowe, C 2016 ‘Cognition and the Evolution of Camouflage’, The Royal Society, vol. 283, no. 1825.
Picture taken from - https://www.pexels.com/photo/animal-green-wildlife-leafs-57021/. Viewed on 08/03/2019


Comments

  1. Tasmin11 March 2019 at 15:44

    A really great start! What do you think the mechanism of evolution was for evolving complex eyes from simple light sensors?

    ReplyDelete
  2. Natalia20 March 2019 at 01:36

    Congrats on your first publication! I really enjoyed it and learned some things from it. :)

    ReplyDelete

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