Sawubona adventurers! Today I bring you a most curious and strange entry, I want to show you the closest living relative of the elephants... the cape rock hyrax. Yes, I haven't gone crazy, this little rodent looking animal shares a clade (branch) with the elephants and manatee called penungulata "almost ungulate". Needless to say, these three animals look nothing like each other on the outside, do they? We will see that now, but let's focus on elephants and hyraxes.
First of all I would like to point out that it all began in the Paleocene (geological period, the first of the Tertiary period of the Cenozoic era) when the first tetithers (branch of Afroterian mammals) appeared, some 65 million years ago, where the common ancestor of these animals lived, from then on they differentiated into several phyletic lines (evolutionary process), most of them increasing their size considerably but they started to differentiate in the Eocene (geological era) which started 56 million years ago, from here the order Hyraciodea (Damans) and the order Proboscidea (Elephants) appeared.
Knowing where the common starting point is, let's review what they still have today that makes them relatives. It is true that a lot of time has passed, and that their outward appearance makes it impossible for us to relate them, but if we do some research, even on the outside there are things that preserve both species and I am going to tell you about them.
To begin with, both elephants and damans do not have a gall bladder, it is an organ that belongs to the digestive system, and is found below the liver, in animals that do have it serves to store and concentrate the bile that they will use during digestion. The lack of this organ is an adaptation to the extreme way of life of these animals, given that a prolonged stagnation in the gallbladder can promote the formation of gallstones, which is why the gallbladder can be absent in mammals that can manage without food or water for a long period of time.
Females of both species share that the 2 mammal glands are located in the armpits, and both male and female elephants and damans have flat nails.
The lungs of both species are attached to the ribcage, unlike us who have pleural space. Here I cannot give you a clear reason, since it has been studied for many years and you do not find a 100% convincing answer. What is more convincing for now is that some common ancestor over there about 60 million years ago was aquatic and evolution caused the pleura to be replaced by thick connective tissue to help change the pressures when swimming in the deep.
Both have glands in their paws, but they do not function like the sweat glands our dogs may have to lower their temperature. These glands secrete a watery liquid which in the case of the damans helps them to keep a better grip on the rocky areas where they live, and it helps them both because it also keeps the palm on their feet cool when walking on hot surfaces such as rocks or sand.
This next peculiarity is shared by males of both species, and that is that they do not have a scrotum, their testicles are inside the body close to the kidneys. There is no answer to this peculiarity since the reason that most mammals have their testicles outside their body is to keep their sperm at an optimal and cool temperature, for their good functioning, but in the case of these animals, it defies all logic.
The last of all their common characteristics is dentition, both have incisors that never stop growing, it should be noted that the skulls are quite similar too. Yes, the elephant tusks are incisors that grow throughout their lives in both females and males of the African species and serve them to search for food, defend themselves or fight with other individuals. In the case of damans, the growth of the incisors is much more pronounced in males, so we can know approximately how old they are, and serve to defend themselves or to fight for territory and maintain it.
This is the end of the list of things these animals have in common, which are very different on the outside, but if we look closely and investigate we can start to see similarities. I hope you liked it as much as I did researching them.
Impilo enh adventurers!
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