Naked Mole-Rat

The naked mole-rat (heterocephalus glaber) is found in East Africa, ranging from Ethiopia and Somalia to northern Kenya. They are small rodents that are around 5-6 inches long and weigh only a few ounces. They may be small, but they make up in sheer numbers. Naked mole-rats live in large colonies of extended families, run by a single queen. Similar to the way termites live, the mole-rat queen is a lot larger and is the only female in the colony that is able to breed. 

Naked mole-rats are well adapted to living underground. Having no hair means that they won't get dirty when they dig and allows them to slide past each other in their close quarters. Unlike what their name implies, naked mole-rats are not moles, they are a totally different specie, and do not have the large burrowing claws like a regular mole. To make tunnels, they use their teeth. Like all rodents, they have bucked incisors that grow constantly. However, the mole-rat's teeth grow outside of their mouths. This allows them to close their mouths while they are burrowing so they don't get a mouthful of dirt. 

Living in such close proximity to each other can mean it can get rather stuffy in a mole-rat colony and hard to breath. However, this does not bother them. Unlike other animals, mole-rats can survive for long periods of time with little oxygen. When we breath (the process is called respiration), we bring oxygen to our blood that brings it to the rest of our body, and more importantly, our brains. If our bodies go for a long time with out oxygen, we can suffer brain damage or even death. 

Not only can mole-rats survive in their low oxygen environment, but they can also survive in highly acidic soil and toxic metals with out a problem, as well as feeling no pain. They also never get cancer and age differently than other rodents for it's size. Normal rodents that are the same size as the naked mole-rat live around 2 to 4 years. Mole rats can live up to 30 years and show no sign of aging. Our bodies are made out of individual cells that have a specific purpose. As we grow, our cells replicate to replace cells that have died or been damaged. As cells replicate, some pieces don't replicate correctly, break down, or stop working. This causes aging. Even at 30 years old, a mole-rat's cells still look fresh and new, like they don't age at all! Mole rat's are like little super heroes!

Source:  The Encyclopedia of Animals, 2006, Per Christiansen. 
Underground Supermodels: What can a twenty something naked mole-rat tell us about fighting pain, cancer, and aging?, Thomas Park and Rochelle Duffenstein, The Scientist Magazine (June 2012), http://www.the-scientist.com/?articles.view/articleNo/32136/title/Underground-Supermodels/(Accessed Jan. 31, 2014).

Deep Sea Angler Fish

The deep sea angler fish is found in the deepest part of the oceans of world. Where they live it is so deep that many of the creatures that live there never see sunlight. This part of the ocean is known as the abyss. The angler fish gets it's name from an appendage on it's head, called on esca, that is uses to lure it's prey toward it. Because it is hard to find prey in their dark home, angler fish can't waste the energy swimming around and hunting food. So instead, it lies in wait, using it's lure to draw other fish towards it's mouth. 

The esca contains glowing, or bioluminescent, bacteria. The bacteria and the angler fish have a symbiotic relationship, which means that they both benefit from one another by working together. When the angler fish catches a meal, the bacteria also get a free meal. So by working together, the bacteria and the angler fish get to eat.

Another strange fact about the deep sea angler fish is that the ones that are seen the most are female. The male is tiny in comparison to the female and acts like a parasite (something that lives off the energy of others). It attaches it's self to the female and glues himself to her. He then looses all other functions except his reproductive duties. 

This is an example of sexual dimorphism, which is when the male or female of the species looks totally different. Many birds also exhibit this; male birds are more flashy than female ones. Like the peacock for example; the male has a long pretty tail with lots color while the female is usually a drab brown. This allows animals to survive in different ways. For the angler fish, it can be hard to find a mate in pitch blackness, so once they find each other, they are together for live. 

Source: The Encyclopedia of Animals, 2006, Per Christiansen