Last month, in a post about the green anole, I mentioned that it was able to change color. Anoles and chameleons are not the only color-changing animals. If you’ve ever caught a frog outdoors in cold weather and it seemed to get lighter as it warmed up in your hands, that wasn’t your imagination.
Backyard Biology has a fantastic explanation of frog skin colors and how they can change.
The ever-changeable, Gray Treefrog. How does it do it?
Green is a popular color for frogs, and birds too, but that lovely green color doesn’t come from a green pigment as you might expect, but from the interaction of multiple layers of specialized color and light-reflecting cells in the upper layers of their skin.
Frogs have three layers of chromatophores (color-producing cells) in their skin. The deepest layer are melanophores that produce melanin pigment giving skin a brown to black color. The middle layer are iridiphores which contain no pigment but instead have mirror like plates capable of producing iridescence, or when viewed from a certain angle, reflect blue light. The most superficial layer of chromatophores are xanthophores that contain a yellow pigment. When the middle layer of iridophores interact with the top layer of yellow-pigment containing xanthophores, you get what elementary school students have learned: yellow paint + blue paint…
The common nighthawk is a swift, graceful flyer capable of catching and eating insects on the wing. Its territorial “call” isn’t really a call; it’s a loud whirring buzz made by its wings as it dives. You’d think such a bird would nest high in a tree, as close to the sky as possible, right?
Nope. The nighthawk doesn’t build a nest at all. It just lays its eggs right on the ground, where their speckled pattern blends in with the dirt and leaves.
I am currently on a botany field trip to the mountains, where I am likely out of cell phone range and not answering comments, but hopefully taking lots of pictures to eventually post. But through the miracle of post scheduling, I’m posting this now! A couple of days ago, LGBT STEM posted an interview with me on their site, so go check it out.
Or just look at this lovely parrot pitcher plant. You’ve probably noticed my fondness for carnivorous plants by now. Or maybe it’s not that noticeable, because doesn’t everyone like carnivorous plants?
In response to The Daily Post’s weekly photo challenge “Connected,” here’s a footbridge that used to connect the banks of a stream. Well, technically it still does, but you probably wouldn’t want to cross it.
Last week I talked about mole salamanders and the ponds they live in. It’s not just mole salamanders using those ponds, though! Today, I thought the ponds themselves needed a post. Mole salamanders, and many other amphibians, tend to breed in what are known as ephemeral ponds, or vernal pools. Whatever you call them, they are just low spots that fill with water at certain times of year, but their temporary nature is what defines them, and what makes them an essential wildlife habitat.
Even though the rainiest season in most of the South is summer, the ponds usually hold water in winter, after the late fall rains. There may be more rain in summer, but it is promptly sucked up by tree roots or evaporated in the heat. In winter, the trees are dormant and the air is cooler, so water is left to saturate the ground and pool in the hollows.
How long the ponds will hold water is an important factor for wildlife. Some of the shallow pools dry in a matter of days. Others have at least a puddle at the deepest point for most of the year. In drought years, almost none of them will have any water at all. Continue reading Ephemeral Ponds
The mole salamander (Ambystoma talpoideum) is not a glamorous-looking creature. It’s small, unassuming, and slippery. It lives in burrows and in small isolated ponds in the woods. It’s mostly dark brown or black, often mottled with a gray or blue lichen-like pattern. It has a broad, flattened head. It looks a little like some artists’ reconstructions of Tiktaalik, and it’s easy to picture it living back when animals were first starting to crawl onto land.
Many southerners will recognize the green anole, aka Carolina anole, aka American chameleon. The scientific name is Anolis carolinensis.
Though sold in pet shops as “chameleons” because of their color-changing ability, they’re not the same as the true chameleons of Africa and Asia.
Green anoles are small, slender lizards that live mostly in trees, but can also be found clinging to window and porch screens. Usually bright green, they can change their color to brown or tan. They have a pink throat fan, or dewlap, which they expand to communicate with other anoles. They are territorial, so what they’re communicating is probably “MY tree! Go away!”
(Arachnophobia: fear of spiders and scorpions. Hemophobia: fear of blood. Ophidiophobia: fear of snakes.)
In any job dealing with wildlife in the field, you’re eventually going to have to deal with things many people find frightening, disgusting, or just plain creepy. I have caught and been bitten by snakes, walked through countless spiderwebs, and waded around in ponds with a thick layer of scum on the surface.
One of my projects in the summer was to trap, measure, mark, and release snakes. To that end, my co-workers and I set up giant X-shaped silt fence arrangements with a trap in the center and buckets as pitfall traps at each end. The buckets were covered with little plywood tables to provide shade. One day I lifted up one of the plywood tops and found this:
That is a pigmy rattlesnake in the bucket. Next to it is a very large wolf spider. On the underside of the plywood is a black widow spider and the dried-out corpse of a scorpion. An arachnophobe’s nightmare.