When winter is drawing to a close and the temperatures begin to warm up, life begins to happen before your eyes. The grass begins to grow, the spring migratory birds begin to move in, the days get longer, and the trees bring forth buds… and pollen. Here at Long Acres Ranch, anytime we have students out in the field for an educational experience, we remind students, and adults, that they are in the animals' homes. Primarily, we remind them that snakes are becoming active with the temperature increase. That is why herpetology is the “ology” focus for the month of April.
What is Herpetology?
Biology is the study of living things. Zoology is a branch of biology that studies members of the animal kingdom. Herpetology is a branch of zoology that focuses on reptiles and amphibians. The Greek word “herpeton”, means “creeping animal” and is where the word herpetology, or herps for short, is derived from. Except for certain reptiles, such as crocodiles and some lizards, most reptiles and amphibians either have no legs or lack the ability to fully lift their bodies off the ground and thus drag their bellies instead. Hence, that is why herps are referred to as creeping animals.
What is the difference between Amphibians and Reptiles?
Herps are cold-blooded which means they cannot regulate their internal temperature on their own and are subject to the change in temperature of the environment. They are also vertebrate animals meaning they have a backbone. As opposed to a nonvertebrate which has an exoskeleton such as crabs or insects. Amphibians and reptiles are located on every continent with the exception of Antarctica. Although they are lumped together under herpetology and have some similarities, there are some major differences between amphibians and reptiles.
Amphibians belong to the class Amphibia and include frogs, toads, newts, and salamanders. Amphibians tend to be more vocal than reptiles. For example, frogs will serenade listening ears at night and especially following a rain. Also, amphibians lack scales and instead have skin. The skin is moist which is often covered by self-made mucus that prevents the skin from drying out. Therefore, they all require a moist environment. A majority of amphibians go through metamorphosis that requires the young to breathe underwater where the eggs are laid. Even more interesting is that a few species of salamanders and one species of frog lack lungs or gills and must oxygenate entirely through their skin.
Something of interest to note is that amphibians' skin is porous. This means that they can breathe through their skin. Because all amphibians' skin is thin and porous, they are very susceptible to toxins in the water. This results in that they are quick indicators of water quality. A healthy community of amphibians that drastically decrease or disappear, not caused by seasonal environmental changes, would suggest that the body of water they utilize has been polluted or affected by a toxin. Because of their permeable skin, this is also why amphibians do not live in saltwater.
Reptiles belong to the class Reptilia and include snakes, lizards, turtles, alligators, and crocodiles. Reptiles have scales of which the surface of the scales are dry. Reptiles will molt or shed their scales, sometimes the whole skin at once, as they grow larger in size. The scales serve as a barrier or protection from the environment around them which makes them less susceptible to toxins.
Reptiles, unlike amphibians, have seagoing species meaning those species can tolerate saltwater such as the American alligator. Hatching from hard or leather-like eggs, the reptile babies look like an adult, but on a much smaller scale. They are born ready to take on the world, with or without their parents. Reptiles may not be considered pretty vocalists because their sounds include hisses, grunts, and a roar or two. However, they still communicate during breeding season and to warn trespassers when they enter their territory.
In Defense of Herps
An excellent defense that some amphibians and reptiles have is camouflage or mimicry. Camouflage is when something blends in with its surroundings or background. Mimicry is when something looks like something else. Both of these defenses increase the survivability of the animal that utilizes this biological adaptation.
Camouflage can be used to hide from predators, but can also be used to hide from their prey while hunting. The most common example would be the chameleon with its ability to adjust the color of its skin to match the foliage it is in. However, some anoles are also able to change their color from light to dark as well. Better yet, there are leaf shaped frogs that blend into the leaves on the ground floor. On that same note, there are a variety of geckos who look like bark, twigs, or leaves to blend in. Snakes also have an uncanny ability to blend in to their surroundings - like the copperhead!
Mimicry has been discovered across the biosphere in all species of organisms. With the study of mimicry, it has been determined that it is not very common among amphibians. This may be in part due to the fact that some amphibians are poisonous or simply the type of predator that preys upon them is not deterred. However, there is a species of poison arrow frog that is not poisonous but rather mimics the arrow frogs who are and is therefore left alone by other animals.
For reptiles, mimicry is more common especially among snakes. A common saying is “red on yellow, venomous fellow, red on black, friend of Jack”. This is to help identify the difference between a venomous coral snake (upper left) and a nonvenomous milk snake (upper right). Even for the untrained eye, at first glance a corn snake might even resemble a coral snake. Or at least give it an extra few seconds to get away. Some snakes will mimic the behavior of a rattlesnake by shaking its tail. Something interesting to note here is that in recent times, rattlesnakes are less likely to rattle their tail to warn nearby individuals.
No matter your feelings about creeping animals, especially snakes, they do have some interesting evolutionary adaptations that make them unique. Reptiles and amphibians play a special importance within the ecosystem as a food source, as population control, and unfortunately, for pollution indicators. Due to habitat destruction and environmental changes, amphibians and reptiles numbers have been in decline. However, the more we understand, the better directed efforts we can put forth to take care of the wildlife around us.