Guest Author - Kimberly Weiss
Reptiles and Birds.
One of my favorite places to go is the Great Swamp in New Jersey. Although it is a pretty good spot for birding, especially for Eastern bluebirds and wood ducks, it is mostly known for its excellence in reptiles. You may get a good bird find there. You will see at least several turtles of different species (sometimes even a large snapping turtle) and sometimes even dozens of snakes.
Some birders are purists. When they go birding, they want to see birds, not reptiles. Others, like myself, like all animals. If I can’t see a good bird, a reptile will do nicely.
I remember reading a humorous article in a birding magazine about this dilemma. It seems like some of the birding-only fans bicker with their reptile-loving fans on nature trips. They don’t want to see a reptile, darn it. They want to see a bird!
Fortunately, a unique solution has arisen to satisfy both sides. It seems that birds are now considered reptiles.
While I knew that birds were considered to have evolved from reptiles, it seems that some taxonomists now think that birds and reptiles are so similar that they can no longer be separated. I read this in the AP Biology textbook that I am using in my day job, a book that prides itself on having the most “cutting edge” information. So is it true?
The last time I taught biology, reptiles—snakes, lizards and turtles—were in Class Reptilia. Birds were in Class Aves. While both birds and reptiles lay hard-shelled eggs and have scales, there were several important differences between the classes. For one thing, while both have “scales”, the “scales” of a bird are much different than that of a reptile. They are actually what most of us call “feathers.” The bones of a bird are very different from that of a reptile, as well. They have air pockets to help the bird remain light enough to fly. And most importantly, birds are endothermic or warm blooded. They maintain a constant body temperature, as mammals do. Reptiles are ectothermic or cold blooded. They must spend a lot of time basking in the sun to keep warm. You never see a reptile living where it is cold, like you see penguins in Antarctica, for example.
And of course, reptiles don’t fly. Well, not the existing reptiles, anyway. Did you ever see “The Flinstones?” Remember when the Flintstones and Rubbles would fly somewhere on a giant flying dinosaur? That animal did exist. It was called a pterosaur (or sometimes a pterodactyl), and it is considered a sort of missing link between birds and lizards. Dinosaurs had a lot in common with birds. Many dinosaurs had feathers, and they may have cared for their young in nests as birds do. They also had similar lungs and gizzards to modern day birds. Some evolutionary biologists believe that birds and dinosaurs were so similar that there really is no practical difference between them. So birds should be considered reptiles, just like dinosaurs.
Bird evolution remains a controversial topic. At one point, the main “missing link” between birds and dinosaurs was an animal called the “Archaeopteryx.” Today, scientists discount the importance of this animal on the evolutionary chain. Some still maintain that birds and reptiles belong in separate classes; others say that birds and reptiles belong together. I personally would not put them together in a class. I think that there are serious differences between the birds of today and the reptiles of today. Still, I understand the rationale behind the combining of the two classes, and I find it kind of ironic, in a way. So many people love the pretty little birds and fear the slithering, hissing, jaw-chomping, creepy reptiles. Wouldn’t it be funny if they were one and the same?