8 Animals That Are Evolving Quickly

Whether it's climate change or other environmental conditions, animals are constantly evolving to better survive. Most people think of animal evolution as being something that takes place over hundreds of thousands or even millions of years. But this isn't the case for the resilient species listed here, including the otherwise slow-moving grove snail pictured here. Take a look!

An animal changing due to climate change is the tawny owl, a common owl in Europe. This owl typically comes in two color variations, either a brownish or a grayish. The gray-feathered owls are more common in colder areas since their colorization helps them stay camouflaged in the snow. However, researchers in Finland found the number of brown owls in their area has definitely increased, according to a study in the journal Nature Communications. The brown owls are surviving better in the chilly (and white) environment and are producing more offspring to survive long-term.

So what the heck is a hybrid mouse? The journal Current Biology explains how a typical house mouse in Germany bred with an Algerian mouse that happened to be resistant to poison. The result? A hybrid mouse that could resist typical poisoning, leading some exterminators to mutter, "Rats." In most instances, the hybrid animals can't reproduce, but that's not true of these sturdy mice.

The brown lizard started moving in on the turf of green lizards, so the latter started to adapt by moving farther up the trees. As they did this, their bodies had to adjust. In a short amount of time (about 20 years), researchers in the College of Natural Sciences at the University of Texas at Austin say the green lizard grew bigger pads on its toes, and it also developed stickier scales to help it hold on. So if you're in Florida anytime soon and you want to see a green lizard, look up!

This is a case where evolution is good for animals but bad for humans. Since humans have used an abundance of chemicals to keep bedbugs at bay, bedbugs have developed thicker shells and tougher nerve endings. Ohio State University has been a leader in information about bedbugs and scientists there closely follow the research on this topic. They say most over-the-counter products available to consumers don't work that well on these pesky insects.

This is one of the most famous examples of animal evolution, and you can find in high school and college textbooks, thanks to researchers in the 1950s and 1960s like Bernard Kettlewell, Cyril A. Clarke and Philip Sheppard. This moth always had a light, mottled version (top image) and a dark, fairly solid version (bottom image). The dark version used to make up only 2 percent of the population, but after the Industrial Revolution, the population numbers changed drastically as the darker moths became far more common. Scientists think that's because surfaces that were once light were darkened by pollution, and the moth had to adapt to survive.

In Europe, banded or grove snails typically have one of two shell colors: lighter yellow or darker brown. Researchers compared snail samples taken in the 1960s with those taken in 2010. A study published in Global Change Biology found that lighter-colored shells are on the rise. They believe this is because temperatures are warmer overall, so the lighter shells help snails stay cooler.

This lizard was introduced to the island of Pod Mrčaru in the 1970s. Because of the change in setting, the lizards switched from an insectivorous diet to mostly plants. This caused the lizards to develop larger heads and they also developed cecal valves, a change highlighted in the journal Proceedings of the National Academy of Sciences. This is unique because the valve helped separate the lizard's intestines to adapt to the new diet. Now that's an impressive physical transformation!

Climate change is affecting all living things, including the pink salmon. Nowadays, these fish are migrating a couple of weeks earlier than they did 40 years ago. It might be easy to think this is just a behavioral change, but scientists say it's more than that. A study published in Proceedings of the Royal Society B looked closely at salmon populations in Alaska, and the researchers were surprised to learn there were genetic changes in the offspring from those from 40 years ago. They aren't sure what this could mean long term, but they suspect it could have an affect on the fishing industry.