It is no secret that the animal kingdom is filled with creatures that have amazing skills and abilities. Animals continue to fascinate researchers and many have surprising talents. Most animal talents are actually sophisticated adaptations from centuries of evolution.
Hermaphroditism in fish
Some fish have the amazing ability to change their sex and some are both sexes simultaneously. Sequential hermaphroditism is when an individual fish for one reason or another changes from either male to female or female to male – this can be the result of hormonal cycles or the environment. Clownfish perform sequential hermaphroditism. Groups of these fish live within an anemone and only the two largest will mate. The largest fish will become female if it is male and will mate with the second largest fish. Many fish that live in the deep sea where population density and light are low have characteristics of both sexes and can spawn with any individual they encounter. Some fish even change sex based on environmental factors.
Unique blood flow in giraffes
Because giraffes are so tall they have developed a specialized heart and circulatory system in order to pump blood to their brain. They require double the blood pressure of other animals in order to fight against gravity. The 25 pound (10 kilogram) heart works extra hard, and then the rete miribale in the upper neck prevents excessive blood to the brain when giraffes bend over to drink. In their legs are special blood vessels which are constantly under immense pressure. The capillaries of any other animal would burst under the same weight, but giraffes have have a tight sheath of skin to maintain the extravascular pressure in the same way that g-suits of pilots work.
Migration of birds
Everyone is familiar with birds that migrate and it is what a lot of people think of first when they think of birds. It has long baffled scientists how so many species of birds manage to perform lengthy migrations without getting lost. Some even fly non-stop when stars are obscured over open ocean so there are no landmarks. Recent research has indicated that birds have an additional sense – the ability to detect the Earth’s magnetic fields. How exactly this sense works is still mysterious. Recently, researchers at Baylor have identified cells in the brain of a pigeon that seem to contain and record information about magnetic fields. We are still unsure how they detect the fields. Some speculate that birds have special chemical reactions in their eyes allowing them to literally see changes in magnetism. Other speculative theories include special neurons in their beaks.
Crocodilian cardiac shunting
Similar to the circulatory system of the giraffe, crocodilians (crocodiles, alligators, and caiman) have a specialized heart. Unlike the giraffe though, crocodiles have the amazing ability to actively shunt blood away from their lungs with no adverse consequences. Crocodilians have a four-chambered heart unlike those of other reptiles, but like those of birds and mammals. Birds nor mammals – not even diving birds and aquatic mammals – have the same seemingly voluntary shunting ability. In fact, if a shunt occurs it is often detrimental. The right ventricle has two aortas and the animals are capable of closing one, the one leading to the pulmonary system, while leaving the other open to maintain blood flow to the rest of the body. Rerouting de-oxygenated blood helps the animals stay submerged for longer without putting a huge strain on their internal systems.
