Through years of evolution, most animals have evolved their own unique defense mechanisms, enabling them to survive effectively in the wild. The squid, a member of the Mollusca class Cephalopod, is a prominent example of evolution by natural selection to adapt to new environments. The newfound predators that hunt by speed and eyesight will be salient, or prominent, to the squids, creating a new environment. These new predators will act as selective forces by changing the environment of the squids causing it to be a more dangerous place to inhabit. This will affect the squid’s ability to avoid harm brought about by the predators. They must learn to adapt their defense mechanisms in order to better protect themselves from these new effective predators. In order to survive and protect themselves, squids use a variety of unique adaptations methods. One such method is using distraction and surprise to avoid harm. For example, in the presence of intruders, squids eject dark fluid from their own bodies. This fluid, which is ink-like in quality will temporarily affect the predator 's vision, allowing the squid time to escape. Also, cephalopods use camouflage to avoid being detected. Squids can change the color of their skin to mimic their environment and hide from predators. The squid is also the fastest of all cephalopods. They use a kind of jet propulsion to move.
Their streamlined shape allows them to propel themselves backward swiftly through the water with little resistance. The funnel enables them to use "jet propulsion." They swim in large schools, which may also give them some protection. Besides being able to move quickly, the cephalopod’s intelligence and acute vision enhance its ability to seek prey, avoid predators, and communicate. These preexisting variations will be able to help the squids to better adapt and survive with this new predator-filled environment.
The squid’s pre-existing variants can be selected for by this new environment.
References: Benjamins, Steven. "Cephalopod Predators." The Cephalopods Page. N.p., n.d. Web. 29 Oct 2012. <http://www.thecephalopodpage.org/pred1.php>.
“Squid”. Columbia Encyclopedia. 6th ed. 2005
"Squid and Octopus." NatureWorks. N.p., n.d. Web. 29 Oct 2012. <http://www.nhptv.org/natureworks/nwep6f.htm>