Sharing the Road
Humans love to build things. Love to change the landscape to fit their desires. We have altered the face of the planet in an unrecognizable way in many places. The land and plants and animals that were living here prior to our development didn't just disappear. Sure we squished many of them with our tractors and mulched others in the process, but those that remain must live on. To live on, they must adapt and learn how to co-exist with human society. We will discuss a few different creatures' abilities to adapt to our terraforming. After reading this I challenge you to try and observe these happenings and maybe even discover some others I haven't mentioned.
We will begin with freeways. These carve the land into segments, and giant hunks of metal traveling at 70 miles an hour pose quite the threat to any animals trying to cross. In effect, it creates a barrier or at least makes animals have to slow down and look for an opening before they cross. We will take the I5 freeway that runs through California as an example. The grazing meadows filled with cows also host many species of small mammals, mice, rabbits, and ground squirrels to name a few. What do all these animals have in common? They are perfect prey for a red tail hawk.
Next time you drive up the I5 or really any freeway, keep an eye on the light posts or telephone wires running parallel to the freeway. On the I5 you will see a red tail hawk every couple miles seated on a telephone pole. These intelligent feathered friends know that whenever a small mammal comes to the edge of the freeway they become exposed, and have to slow down. The mouse or rabbit will have to make a decision about whether to cross or not and at this moment the hawk will swoop down and have himself a tasty snack. Personally the most fascinating part of this is the even spacing of the hawks. They have their territories entirely figured out between them, take note of your odometer while you drive the I5 and see if you can figure out the size of their hunting grounds.
Sometimes the mouse, rabbit, or even bigger creatures like racoons, or deer for example might try to cross and be hit by a car. Something we have aptly named roadkill. Ever wonder why roadkill always seems to be gone by the next time you drive by? That's because other creatures have specialized in exploiting this part of human society. The main protagonists are vultures, crows, and ravens, who happily swoop down on the carcasses and enjoy the sunbaked tarmac flavored meal.
Freeways also impact animals in a slightly different way. For example, mountain lions have huge ranges sometimes reaching 390 square miles! It's inevitable that freeways may run through this territory. Mountain lions often will choose to just avoid the freeway entirely and this can end up segregating their populations and make finding a mate near impossible. Some scientists have noticed this conundrum and began working on animal crossings to go either over or under a freeway. This is great in concept, but just like a freeway it incurs its own form of traffic. If there is only one road and everyone needs to cross it, that creates a traffic jam. However, and thankfully, in human society everyone just sits bored in their cars. But in the animal kingdom, some of those in the traffic jam are mountain lions, coyotes, and bobcats. While others are those poor small mammals.
These predators have understood the congestion of prey items in these animal crossings and will often set up camp there, jaws wide open. Animals are incredibly smart, much smarter than we give them credit for. Even down to the littlest ones. Spiders actually utilize the same tactic on these animal crossings, and lie in wait for crossing insects.
Can you think of another way spiders use human society to their advantage? Ever notice your outdoor lamps are always covered in cobwebs? It's no mistake spiders have eight eyes and they use them. They see that insects are careening around your lamp, and they realize that casting a net into a school of fish works much better than casting into the open sea.
We can go on and on, racoons in your trash, bats sleeping in your rafters, and mice in your cupboards, just to name a few of the sneaky moochers. Next time you're at home take a close look around and see what kind of critters might be living rent free.
Photos taken by Alex Havasi and Isaac Yelchin
Isaac Yelchin is foremost a herpetologist. He studies lizards, frogs, newts, and the like. Specifically, he spends all day and night thinking about what it is like to be an animal. What are the animals thinking about? What is their perspective? When he should be working, he sits and stares at his pet lizard asking himself these questions.