When I was a kid, my parents gave me a Mattel product called a “Thingmaker“. It consisted of a hotplate oven and a series of molds that allowed you to make replicas of all kinds of “creepy” animals like snakes, spiders, worms, and of course insects. Into these molds you could pour a plastic goop that would be heated and cured, and then would harden into a rubbery replica of the animal in the mold. I loved the Thingmaker. I cannot even begin to tell you how many of these creepy crawlers I made and played with. Best toy ever …
As I look back on it now, I wonder if that toy was one of the things that got me started with enjoying what herpetologist Kate Jackson describes as the “mean and lowly things” in her book by that title [I think the original reference was made by Aristotle].
Why do I like snakes and frogs and spiders?
People often ask me, “Why snakes and frogs? Why spiders?” or “Why can’t you like the cute, cuddly, and furry things?” Don’t get me wrong: who doesn’t love a chinchilla, or a golden lion tamarin, or an elephant, or a panda bear? I love all of these animals too. But I have a special place in my heart for those animals which other people find unlovable. For those animals that are killed without any forethought – because they are considered “mean and lowly”, even though they were created by a Creator that said they are good. These are the animals I care about.
Of course a lot of misconceptions and assumptions go into the way people feel about these animals. For example, the false idea that snakes are slimy and gross. Snakes do not produce a slimy coating on their body, and in fact are covered with scales that give them a dry, leathery feeling. Those scales are made out of the same thing as your fingernails – the substance known as keratin.
Snakes are really aggressive and they will chase after you. Snakes are more afraid of you than you are of them. So when a snake feels threatened, its first inclination is to find an escape route. If there is none, a snake will do the same thing a person would do – defend itself. For a snake, it means showing a threat display, such as the hood of the cobra, the shake of a rattlesnake’s tail, a rigid S-shaped posture, hissing, mouth gaping, striking, and so on. But snakes DO NOT CHASE PEOPLE. If you happen to be moving in the same direction as the snake’s escape route, it might seem so, but that is not the case. The snake wants to get away from you.
Here are a few other things I find interesting about creepy crawlers …
Are Creepy Crawlers Cold-Blooded?
One of my favorite pet peeves is when people call reptiles “cold-blooded”. People throw that phrase around without even knowing what it means or suggests. Yes, I know that is what they taught you in school, but don’t believe everything a teacher teaches you (ha ha). Investigate for yourself. Reptiles cannot retain the heat that their body produces (ectotherms) naturally, unlike mammals that can maintain a nearly constant internal temperature. Instead, reptiles have to get their heat from their environment so their body temperature is the same as that of their surroundings (poikilotherms). So let me ask you: if a snake or lizard is basking in the sun, do you really think their blood is cold? Not at all! So this term is a misnomer.
“Aren’t all snakes ‘poisonous’? What about frogs and toads?”
If I had a nickel for every time I heard this one. Out of the more than 3000 species of snakes that exist on Planet Earth, only about 600 (20%) are venomous. Only a very few, some of the keelback snakes of Southeast Asia and Japan, are actually poisonous – they store the poison produced by the toads that they eat and secrete it when threatened.
What is the difference you might ask? Quite a big difference, actually. A toxin is a chemical or mixture of chemicals that cause harm to a living being. Venom contains toxins that have to be injected meaning it goes directly into the blood stream or the lymphatic system – the same idea as a hypodermic needle. Poison is a toxin that is ingested (eaten), inhaled (breathing), or absorbed through the skin.
So snakes that use fangs to inject toxins are venomous. Snakes can have one of three types of fangs. Some have short fixed fangs in the front of the mouth (cobras and mambas), while some have large foldable fangs in the front of the mouth (puff adders, rattlesnakes, and fer-de-lance). The last category is snakes that have fangs in the rear of their mouths, and these generally have to chew the venom into their prey. One time my colleague, Dr. Cossel, and I captured a brown debris snake in Tinamastes, Costa Rica. Not knowing much about it, Dr. Cossel went to photograph the snake and it latched on and chewed on his hand for a couple of minutes, leaving behind a very sore, throbbing bite from its weak venom. And here is one you would never have guessed – the garter snake is rear fanged and venomous – but the venom is too weak to affect most humans.
Snake venoms are generally found in three different categories: cytotoxins (destroy cells and tissue), hemotoxins (interfere with the blood’s ability to coagulate and clot), and neurotoxins (interfere with nerve transmissions that affect important muscles like the diaphragm which controls breathing).
Frogs and toads, on the other hand, can be poisonous. They can either manufacture the poison themselves in special glands (such as the bufotoxin secreted by toads from their parotoid gland), or acquired from the food they eat and stored (generally beetles and ants). If you get the poison on your hands and then forget to wash and subsequently stick your hands in your mouth or eyes, you can be in for a real unpleasant time. I did that once after handling a milk frog in Palo Verde National Park in Costa Rica. It impaired my vision for nearly 1/2 hour.
“What about spiders? Aren’t all spiders poisonous?” In fact, all but two small groups of spiders do have venom glands, but here again, it is a question of whether the venom is able to cause harm in human beings that is at question. Most venoms are made to target their prey items and may not be effective on humans. However, there are some spiders that have very toxic venoms, including widows, brown recluse, and funnel-web spiders. Tarantulas are a large group of spiders, and their degree of toxicity varies by species. The Mexican red-legged and Chilean rose-haired tarantulas are often used in educational programs because their venom is less toxic to humans. If you were bitten by one of these it would be very similar to a bee sting.
There are lots of other things I would like to share about “creepy crawlers”, but I will save those for another blog post. Hope you enjoyed this one. Until next time.
Tending To the Garden 
Leave a comment