I confess. I expected tonight’s topic, reptiles and amphibians, to be about as interesting as the seatbelt lecture on planes. They just never have been my thing, so Sarah’s got her work cut out for her just keeping me awake!
First up was a review of Taxonomy and filling out a chart with the distinctive features of each of the six groups of reptiles/amphibians. For example, frogs and toads start out with gills like fish and then develop lungs when they change from tadpoles to frogs. That’s pretty amazing when you think about it.
Tortoises live mostly on land while turtles live mostly in water. But that’s just an American concept. Everywhere else, turtles are turtles wherever they live except in England where they call water turtles “terrapins.”
Sarah made us all laugh when she said that turtles’ backbones are fused to their shells so those cartoon turtles that jump out of their shells and run off in T-shirts and boxer shorts ain’t happenin’.
The reason snakes can open their mouths so wide is that they have a double-hinged jaw and a split in the center of their bottom jaw, so the whole contraption just expands when needed to swallow prey wider than they are. The lower jaw moves forward as the prey comes in and then moves backward to drag it down their throats. This action repeats until the whole thing is swallowed, then the jaw just clicks back into its normal position.
Did you know that snakes don’t have ear holes? Unlike lizards which do, snakes only “hear” vibration, not sound. Another interesting fact is that snakes have an organ in their mouths that lets them sample the air with their tongues to “smell” food and prey.
Next up was Adam Fink, the keeper of our reptile, amphibian and insect residents. Adam’s been a zookeeper here for nearly a decade and has taken care of nearly every animal in the Zoo.
He might not look it, but let me tell you, Adam’s one funny fellow and you have to write really fast to keep up with him. He zipped through a slideshow of everything he has here except insects. Here are a few highlights:
Alligators, only show their upper teeth when their mouths are closed. The males do a glitzy water dance to attract mates and ours do it even though we have no females. You can watch a fun video of it here.
Our 5 Aldabra tortoises weigh in at up to 300 pounds and the oldest is 120 years, we think. One is a little under the weather, so Adam makes her fruit smoothies served on a bed of lettuce. Lucky tortoise!
Chuckwalla Lizards have internal air sacs they can puff up so that when they escape into rock crevices, predators can’t get them out. Neither can Adam, so they just stay in there until they calm down.
The difference between venomous and poisonous is the difference in how poison is used by the animal. Venomous snakes have fangs that inject toxins into would-be predators. Poisonous frogs excrete toxins through their skin, so predators have to bite them or pick them up to get affected.
There are only two types of venomous lizards and our Gila Monsters are one type.
Our Sonoran Desert Toads, on the other hand, are poisonous. They secrete an hallucinogen from glands behind their that is strong enough to kill a dog but usually not a human, so native Americans used this toxin as a ritual “mood enhancer.”
The Poison Dart Frogs aren’t poisonous in captivity because they don’t get eat kinds of ants and bugs that make their poison.
Of the three ways snakes can kill prey, boas first bite down, wrap their body around their prey, and then they squeeze so hard it stops the dinner-animal’s heart. Nice. But I guess this is no worse than killing their food with venom or beating it to death with a thrashing as other snakes do.
The Emerald Tree Boas have about the longest teeth of any nonvenomous snake. They give live birth to red babies that gradually turn green as they grow up. The green dots on this baby will gradually expand to turn him green all over.
Our Colombian Red-Tailed boa is over 9 feet long and weighs 48 pounds, so you can imagine how hard this gal can squeeze.
All snakes are carnivores: they only want meat. But that led to the question: Exactly what is meat? Are bugs meat? Are fish? Well, the answer is, any living thing that’s not a plant is an animal and all animals are meat. Simple.
We can keep the snakes and frogs together because snakes don’t bother with those little creatures. They want their meat served warm, so cold-blooded frogs and toads just don’t do it for them.
Only male frogs croak. Did you know that? They do it to call their mates.
That’s just a sampling of the dozens of animals facts we learned about in Adam’s Flash Tour. I admit, this was really fascinating and I can even see myself someday giving tours of our RAD (Reptile, Amphibian Discovery) Room.
Tonight’s homework is a fill-in-the-blanks quiz that will send us diving into all the handouts we have for each animal and their classification systems. Want to try one?
Q: Snakes can swallow prey larger than their own heads by the _____________bones which let their jaws open vertically and their ____________ _____________ which let them stretch their jaws horizontally. (We need the technical names here)
Answer in my next post. See you Saturday,