7 Animals That Are Evolving Right Before Our Eyes

By 2005, it was estimated that the tuskless population had risen to between 5 and 10 percent. And it's not just happening in Asia, either. One African national park estimated their number of elephants born without tusks was as high as 38 percent. It's natural selection in action: either lady elephants are deliberately choosing tuskless mates, or the only boy elephants surviving into breeding time are the ones born without tusks. Either way, that tusklessness is getting passed on.

Which is incredible, because it's not like tusks are the elephant version of wisdom teeth. They're weapons and tools, and they're needed to dig for water and roots and to battle for the love of a lady. Which means nature decided poachers are a greater threat to the elephant's existence than its diminished ability to forage or to score.

Maybe you think you've got a smart dog. Maybe you've given him a monocle, named him Dr. Tesla Sagan and taught him how to roll over every time someone recites pi. But while you and Brain the Dog were perfecting parlor tricks, the stray dogs of Moscow have evolved to master the city's subway system.

Today, there are around 35,000 strays roaming Moscow, as dog catching fell behind when the Soviet Union collapsed. Over several generations of breeding, those dogs have gotten very, very smart. If Lady and the Tramp II: Scamp's Adventure taught us anything, besides some sweet-ass songs, it's that street dogs have to rely on their wits to get vittles. And since only 3 percent of Moscow's strays survive long enough to breed, only the toughest and more importantly, the smartest, end up procreating.

Among these Einstein strays, hundreds have taken up residence in the underground metro stations and have freaking learned how to travel their territories via subway train. They'll stand and wait for the train, just like everyone else, then sneak on, go to sleep, and get off at their stops. Day after day. Scientists figure they use smell and the recorded names of stations to navigate.

And that's not all they've figured out. Roving gangs of begging dogs have learned how to send out the smallest and cutest among them to do their begging. And big dogs have learned the bark and grab: jumping and barking at on a person eating a snack, making them drop it, then pouncing on the dropped food.

You know what this means, guys? We are one Billy Joel song away from a real world Oliver and Company on the streets and subways of Moscow.

From 1947 to 1976, the Hudson River was on the business end of some of the country's most egregious water polluting. Specifically, General Electric's 1.3 million pounds of PCBs, which single-handedly turned the river into one of the country's worst Superfund sites.

So you'd think that the animals living in the Hudson would have either completely died off or mutated into hilarious pizza-loving crime fighters -- and you'd be mostly right. But only because no one told you about the Atlantic tomcod. Over the past 20 to 50 generations, the tomcod has done something that would usually take thousands of years or a comic book origin story to pull off: They've evolved immunity from the poison in their water.

Most fish have a receptor gene that contains a protein which regulates the effects of toxins. The tomcods have that gene, but over the past few years, their version has dropped six base pairs, the part of the DNA that toxic molecules stick to. Think of those base pairs like an innocent woman's boobs, and the toxins in the water as Andy Dick's molesting hands. The toxins seek out and grope the crap out of DNA that have them, which triggers a chain reaction of mutations. Without those base pairs, the toxins slide off the gene like hot lard on a Slip-n-Slide.

What must have started as a freak mutation eventually became the only thing keeping the fish alive. And the best part? Eating the tomcod renders humans immune to all industrial toxins. (Just kidding. They'll definitely give you super cancer.)

The interesting thing about lizards is how readily they submitted their allegiance to an upstart rock singer with way more interest in whiskey and mysticism than policy and governance. The other interesting thing about lizards is how adaptable they are.

Take the southeast fence lizard, for example. When fire ants were accidentally introduced to the States about 70 years ago, the fence lizard found itself defenceless against them. The ants had no natural enemies, and it only took 12 of them to take a lizard down in about a minute. Seventy years later, the lizards that live closest to the port where the ants were first introduced have evolved an unlikely strategy for dealing with their antagonists. How unlikely? Well, there's a dance involved, which makes these animals the first on record to employ the West Side Story method of self-defense.

Check it:

While other lizards respond to ant attacks by "sitting still, just hoping the ants would go away," these smooth operators developed an ant-shaking shimmy that they've passed on to their kids. And those kids have longer legs for quicker get-aways. Just so we're clear: Nature, not weird daddy issues, has created leggy lizards that thwart attackers through shaking what their mommas gave them.

But maybe a lizard defense developed over a few generations isn't impressive to you. If that's the case, you should meet the lerista skink. Because, while the fence lizard was getting better at dancing, these skinks were watching their dancing careers end right before their eyes. That is, their legs are going away.

Which is why some of these skinks have little T-Rex nubbin arms, and others don't, like snakes.

Apparently, slithering through the Australian sand is easier than walking through it, and these limb-shedders have adjusted. Of course, by that logic, you'd think humans would have evolved roller skate feet and Go Go Gadget arms by now, but we'll leave that conundrum for Darwin.

In 1971, scientists introduced 10 Italian wall lizards to an island in Croatia, but right after they dropped them off, the Croatian War for Independence prevented the researchers from following up on their little lizard guinea pigs. In fact, the scientists couldn't get back to the island until 2004. When they did, they found 5,000 lizard descendants who had not only annihilated the entire indigenous lizard population, but also rewired the shape of their own innards to accommodate the local diet.

Before their introduction to the island, the wall lizards were carnivores, so their digestive systems weren't built for leaf-eating. But on an island short on insects and long on plants, a strictly carnivorous stomach would be a one-way ticket to Deadville. So the lizards developed things called cecal valves, which were muscles that slowed down the process of food digestion and gave them more time to break down plant cellulose. But growing new gut muscles wasn't all the lizards had up their sleeves. They also grew bigger heads for stronger bites, and dropped territorial defenses.

Scientists said evolution this rapid would be like humans developing another appendix over a few hundred years. Or better yet, Americans spontaneously evolving butt muscles that turn digested corn syrup into car fuel. That last one sounds pretty awesome, actually. Get on it, evolution.

Then you have the three-toed skinks which come from Australia -- where the lizards are apparently gearing up for some kind of uprising, V-style. See those blobs under Mommma Short Arms' skin?

Those are eggs, which you'd expect. But her babies are going to exit her body alive, like some kind of freaking mammal.

Other lizards of the same species are still laying their eggs on the ground, as Xenu intended. But scientists think the three-toed skinks in harsher mountain climates have found it more efficient to keep their young in their bodies longer, because laid eggs are more vulnerable to weather and predators. And to accommodate the live birth of her lizardlings, her uterus is secreting calcium to her embryos, which is actually the beginning stages of developing a placenta. A LIZARD PLACENTA.

Before there was such a thing as "environmental awareness" or "clean air laws," factories lived the lives of rock stars: raw materials came in, smoke, waste and soot came out. No regulations, no apologies, no craftily staged PR campaigns proving they were really the good guys all along. As a result, 19th-century England was a craphole of a country. Soot was everywhere; trees, buildings, streets, children, waistcoat stores -- everywhere.

In the midst of all this sootiness was the peppered moth, just minding its business, trying to get along in the world. Here was what it looked like:

The peppered moth's mottled-grayish color was just about the same color as the lichen and tree trunks that the moths rested on. Which was important, because moths are bird food and birds can't chomp on things they can't see. BUT, as the trees trunks got sooty and the lichen died from pollution, the light-colored moths stuck out like sore thumbs. They also got eaten.

It wasn't long before people noticed peppered moths started turning the color of filth-covered trees:

These moths blended in with the trees nicely, and black became the new black of the moth world. Within 50 years of getting noticed, 98 percent of all the peppered moths in England were black. And we should note that it wasn't just English moths who went black -- American and continental European moths changed colors during the Industrial Revolution as well.

But the story doesn't end there. Over the 20th century, England cleaned up its act and the tree trunks went back to tree trunk color ... as did the moths. That's right, evolution doesn't just plow relentlessly forward. It goes whatever damned direction it needs to.

For anyone who's ever regrettably accepted a late-night booty call from an unfortunate looking associate, you can probably sympathize with the polar bear. Between the melting of the Arctic ice caps, ocean pollution and their obvious issues with obesity, some polar bears have found getting a sexual hook-up as hard as the rest of us find getting a gallon of gas for under two bucks.

Enter the grizzly bear. Ha ha, no really. Polars and grizzlies have decided it's time to know each other biblically, and this time without the involvement of an ark and a horny old man. Not only have they started boinking in the wild, they're also making babies. Grolar bear babies.

The cutest thing about grolar bears is how they get together and stare down evil by the power of the light radiating from their tummies. No wait, we got that wrong. The horrifying thing about grolar bears is how they have carnivorous polar bear behaviors in bodies that are adaptable for warmer climates. So while the grizzly diet is 80 to 90 percent plants, the polar bear feeds strictly on the flesh of other animals. This is why captive grolar bear babies stomp their toys around -- like they would stomp a seal to death.

So, the good news is that in the face of climate change, evolution finds a way to keep on keeping on. The bad news is that we just might lose our cuddly Coca-Cola loving friends of the North forever. Because the characteristics that allow a polar bear to thrive in extreme conditions are going to die out among the grolar mudbloods. After all, if the planet is getting warmer, why would the next generation need those traits at all?

And did we mention how, unlike mules -- which are the sex fruit between donkeys and horses -- grolar bears have proven fertile? So, in order to preserve the racial purity of the polar bear, it's going to have to avoid miscegenation with its brown neighbors. Not coincidentally, that's the exact platform of the Polar Bear KKK.

Kristi Harrison is one Billy Joel song away from being an uptown girl. She's also an editor for Cracked and a Twitter user.

We've got plenty more on animals in our bestselling book.

For more ways Mother Nature is flipping the bird to humans, check out 5 Species That Seem to be Trying to Take over the Earth and 5 Diabolical Animals That Out-Witted Humans.

And stop by Linkstorm to discover how being a troll devolves human beings.

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