The Brain Scoop:
Crocodiles vs. Alligators
The order Crocodilia belongs to an ancient group of reptiles that began evolving 83.5 million years ago. To think that such animals can exist largely unchanged for literally millions of years is fascinating and humbling; it’s remarkable to think that such lifeforms can exist within changing environments and continue to persevere.
This episode was produced, filmed, and edited by Tom McNamara, a new addition to The Brain Scoop’s team. We’re thrilled to have him working with us! He didn’t even pay me
muchto say that.
Asked by stonetemplepilots
Iguanas reach sexual maturity around 18 months of age so you should be able to tell if she is female by now and she may start producing eggs. I personally don’t advocate for spaying iguanas unless we have a history of a problem. If you are providing the proper husbandry for her she should have no problem laying a clutch of eggs. That being said things can happen and you should be prepared to get her to a vet if she becomes egg bound or has any other reproductive issues.
A skilled reptile veterinarian should have no problems with an iguana OVH and it shouldn’t be “hard” on her. Sometimes once the ovaries are removed females can become aggressive for awhile because their adrenal glands are producing testosterone and there is no estrogen to balance it out. Usually this goes away on its own but it can be upsetting for owners.
I would make an appointment with your vet and get a wellness exam done so that any problems can be found now and discuss the concerns you have and they will be able to guide you in the right direction.
Asked by Anonymous
This is difficult to answer without looking into which specific lizard species you mean by lizards in India and checking each species. However, as a colour mutation, white pigmentation (due to leucism or albinism) is relatively common. So it would be entirely possible that leucism has been recorded in lizard species native to India.
Anyone know of any specific recorded cases?
California Nightsnake (Hypsiglena ochrorhyncha nuchalata) - San Mateo County, CA
Nightsnakes are small, nocturnal snakes native to much of the western United States. Primarily lizard eaters, these snakes envenomate their prey with fangs located towards the back of their upper jaw- hence labeled as a “rear-fanged” colubrid. Other examples of rear-fanged (opisthoglyphous) snakes include Hognose Snakes and Ring-necked Snakes, amongst many more throughout the world.
The nation has Punxsutawny Phil the ground hog to prognosticate the coming of spring. We have Texas horned lizards (Phrynosoma cornutum) to announce spring’s arrival. Horned lizards are starting to come out of hibernation and our first horned lizard encounter this year was on 10 April.
(via: Texas Parks and Wildlife)
casual reminder that despite their name sand boas really shouldn’t be kept on sand.
Not that I want to get into any arguments about the captive care of animals, but I must respectfully disagree on this point. Many species of erycine snakes do in fact live on, and especially in, relatively fine-grained sand. Keeping them on that substrate is unlikely to be a problem. They are one of the few desert animals commonly kept in captivity that are actually suited to being kept on sand (Scincus scincus being another notable species). It does not pose a risk to their eyes, and is unlikely to be a risk to their respiratory system either.
It should be noted, however, that Gongylophis colubrinus (the kenyan sand boa) is typically found in association with sandy soils, and so a mix of fertiliser-free potting soil (or your preferred ‘reptile-friendly’ soil) and sand might be more appropriate for it than pure sand.
It should also be also be noted that most naturally occurring sands are not as fine as the sand typically used in terrariums.
The priority with sand boas should be any kind of loose substrate that is sufficiently thin that it can be burrowed through with ease. If you want to use sand, there is ecological support for that decision. However, many keepers use aspen shavings because they are easier to keep clean and don’t weigh as much as sand.
Even so, for the sake of minimising risk to the snake, you should probably avoid feeding on the same substrate. That will increase the risk of impaction, which is a risk on any loose substrate (although a lesser risk than most people assume).
"Rainbow Snake" (Farancia erytrogramma)
Sometimes known as the “Eel Moccasin” the rainbow snake is a species of nonvenomous colubrid snake that is endemic to the coastal plains of the southeastern United States, ranging from southern Maryland to southeastern Louisiana. A small population once inhabited Lake Okeechobee in southern Florida, but said population was declared extinct as of October 2011.
Rainbow snakes typically inhabit aquatic habitats, ranging from cypress swamps and marshes to creeks, slow-moving streams and sandy coastal plains. Their diets consists mainly of eels and other fish, but they will also feed on small amphibians as well.
Image: Alan Garrett
The beautiful Emerald tree boa, Corallus caninus (Boidae), plays an important ecological role in their habitat, helping to control small mammal populations, especially rodents, which can be pests near human settlements.
It is a neotropical species, found in lowland tropical rainforests in the Amazonian and Guianan regions of South America.
Specimen shown was photographed in wild.
Finally I decided to buy myself a sexing probe kit. These probes are how snakes are sexed and the various sizes are used for various sizes of snakes. The end with the ball on it is lubricated and then inserted into the vent of the snake and then gently turned around and inserted toward the tail. In males the probe will be able to be inserted further because it will be inside one of the hemipenes.
This is the most reliable method for sexing older snakes. Hatchlings can have their hemipenes “popped” out of the vent with gentle pressure but once they are more than a few weeks old they have much greater muscle control and can prevent them from being everted.
It is very important that someone with lots of experience sexing snakes does this because it is easy to puncture the hemipenes of a snake with a probe or even rupture through the blind sac of female snakes.
Turtles that eat bone, rocks and soil, and turtles that mine
by Darren Naish
My huge friend and colleague Mathew Wedel owns a Box turtle Terrapene carolina. It’s called Eastie… don’t judge; this is because the animal is an Eastern box turtle (or is she? I wonder if Eastie is a Three-toed box turtle). Anyway, Eastie recently found part of a deceased rat’s head while on a backyard jaunt, and proceeded to deliberately snip away at the broken braincase and eat the bone fragments. This bone-eating carried on for about 20 minutes, and Matt thought it interesting enough to take the photo you see here (TL).
The eating of bones – osteophagy – is well known for turtles, has been recorded in several species, and is observed easily enough in species kept in captivity (like Testudo tortoises). Whenever this subject is mentioned (believe me, it’s always cropping up in conversation), many people recall the photo in David Attenborough’s Life on Earth that shows an Aldabran giant tortoise Aldabrachelys gigantea* scavenging on the carcass of a conspecific (Attenborough 1984) (TR).
As you can see here, it’s not entirely clear what the tortoise is doing, but it looks like it’s gnawing at dried skin and muscle, not bone. Incidentally, the photo was taken by Attenborough himself. I did used to have a very neat photo showing gnaw marks that a pet tortoise (belonging to my late friend and colleague David Cooper) left on a cow bone – to my frustration, I can no longer locate it…
(read more: Tetrapod Zoology - Scientific American)
photos: Mathew Wedel, David Attenborough, and Utahcamera
* Yes, it is actually a 3-toed Box Turtle (T. c. triunguis)
Asked by Anonymous
You are right that it is a very broad question to ask about such a huge group of animals. In general arboreal species have much better vision than fossorial ones. Snakes do have rods as well as cones so I assume that they can see some colors but I am not sure if they are dichromatic or trichromatic. Most likely they are dichromatic which makes them able to distinguish lots of shades of grey but only able to see shades of yellow and blue.
I honestly am not sure about night vision in snakes because the majority of snakes that are nocturnal also have heat pits which supplement their vision. And as you stated all snakes have a Jacobson’s organ which allows them to “taste” their environments so eyesight does not have to be that great. I don’t think anyone knows exactly how snake’s brain interpret visual information, information from the heat pits, and info from the Jacobson’s organ but we tend to think of it as vision with overlays of the other information. Think of any heat vision camera clip you have seen with the various colors representing temperature, this may be how they view their environment.
Oxyrhopus melanogenys (Dipsadidae), known as the Tschudi’s False Coral Snake is a nocturnal species which is found in wet and dry tropical forest of South America .
The body color pattern in this species is in triads of black bands (black-whiteblack-white-black, separated by red or orange inter-spaces), and the top of the head and the snout are black .