All turtles, both aquatic and terrestrial, are located within the order Testudines, which is a very old group, although they have significant anatomical differences with the fossil records found. Turtles are peculiar animals, generally harmless, that rather suffer the consequences of the impact of human actions, which has put many species at significant risk.
We invite you to continue reading this article on our site so you can learn about various turtle curiosities.
They lack teeth
Turtles do not have teeth, however, this is not at all a limitation to feeding, since some species, such as the leatherback sea turtle (Dermochelys coriacea), have somekeratin structures on the palate, around the jaw, and even into the esophagus, which help them retain and process food.
On the other hand, various species, such as the green turtle (Chelonia Mydas), which does not have teeth or the keratin structures mentioned above, rely on the toothed shape of its jaw to hold the algae or the vegetation on which they feed when they are adults.
They don't have vocal cords
One of the most surprising curiosities of sea and land turtles is that they lack vocal cords, however, this does not prevent them from emitting various types of soundsfor communicating. Although we cannot clearly hear the sounds made by these animals, they do, in fact, make them of different types and frequencies. For example, tortoises make certain sounds, mainly during mating.
They lack ears
Another curiosity about turtles is that they don't have an external ear, that is, they don't have ears, but they do have an auditory system made up of the middle and inner ear, which allows them to hear. Another particular feature is that its eardrum, unlike other reptiles, is surrounded by the bony labyrinth and not by scales.
In this sense, despite the fact that turtles lack ears, they not only manage to hear, but also communicate through various types of sounds and frequencies as mentioned above.
The shell is part of the spinal column
The most distinctive feature of the Testudines is, without a doubt, their peculiar shell, which provides some protection against some predators and blows, although its hardness varies from one species to another. This structure is not an exoskeleton, it is a modification of the animal's rib cage, which is also part of its spine and ribs.
This structure in many species is formed by various bones and a thick covering of keratin, with the exception of some cases, in which the shell is softer because it is made up of a thick layer of skin.
Not all have the same type of neck
All turtles are grouped in the order Testudines, but are divided into two suborders:
- Pleurodira (lateral neck): those turtles that can move their heads sideways are located, as the neck vertebrae flex laterally.
- Cryptodira (hidden neck): in this group are those that are capable of retracting their heads inside of the shell, because in this case the neck vertebrae can be flexed vertically.
There are giant species
Within the land tortoises there is a group of 12 living species that are known as Galapagos giant tortoises, being the largest tortoises that currently exist. Although as we mentioned there are several species, some of these can weigh about 400 kg and measure 1.8 meters.
There is also another giant species that inhabits an archipelago in the Indian Ocean, known as the Aldabra giant tortoise (Aldabrachelys gigantea). This species is the one shown in the image.
They communicate before birth
One of the curious facts about sea turtles is that, when they are still in the egg and are not far from hatching, they are able to hear the sounds they make the females grouped in the water, which they do to guide the young. The hatchlings also make certain sounds to communicate with the rest of the hatchlings that are yet to be born and, in this way, synchronize for hatching.
Temperature determines sex
Another curious thing about turtles is that the sex of the hatchling is determined by temperature. Thus, in several species of turtles, the temperature of the medium where the eggs develop determines the sex of the embryos, however, there is no single process:
- In some cases, high temperatures cause more females to form and fewer males.
- In other cases, males form if there are intermediate thermal conditions, while females form if the temperature is in one of the ends.
There are even species, such as the Chinese pond turtle (Mauremys reevesii), in which the embryo moves within the egg to select better temperature conditions, which influences sex determination[1].
Do you want to know more about this topic? Find out how turtles are born in this other article.
They are very long-lived
Turtles while they are in the egg and when they are born are very vulnerable, mainly those that live in natural spaces where there are predators that lie in wait to feed on them. However, they are animals that grow rapidly, which allows them to develop to protect themselves mainly by their shell. Once mature, these animals slow down their development and age slowly, giving them a significant longevity of more than 100 years, as is the case of the Santiago giant tortoise (Chelonoidis darwini), among others.
As a curious fact about turtles related to this point, the Guinness Book of Records lists one of the oldest turtles we know, Tu'i Malila [2], who died at the age of 188. Likewise, in 2006 Adwaita died, a giant Aldabra tortoise that lived in a zoo in India and is suspected to have been more than 250 years old, although it is not known exactly. In the image we see Adwaita.
Many species are in danger of extinction
We end the list of curiosities about turtles with one of the most devastating data, and that is that there are not a few species of turtles that are threatened for various reasons. For example, in the case of marinas, aspects such as climate change, pollution, hunting, bycatch and excess boats, have generated a significant impact on these animals.
We can mention some cases of turtles that are in danger of extinction. For example, both the leatherback sea turtle (Dermochelys coriacea) and the loggerhead sea turtle (Caretta caretta) are considered vulnerable; the green turtle (Chelonia mydas) in danger of extinction; and both the critically endangered hawksbill turtle (Eretmochelys imbricata), the Spanish giant tortoise (Chelonoidis hoodensis) and the flat-tailed turtle (Pyxis planicauda).
If you are concerned about this as much as we are, do not stop investigating and discover in this other article How to help sea turtles, which are among the most endangered.
