Animals such as crocodiles and alligators living in polluted environments have evolved a strong immune system against cancer development. Gut bacteria in these animals produce one or more antitumour molecules to thwart cancer.
Immune system: The crocodile has an optimal immune system. It is almost completely immune to infection with viruses and bacteria (natural antibiotics), able to eat rotting carcasses and swim in contaminated water without being affected.
They are not totally immune to microbial infection, but their resistance thereto is remarkably effective. The immune system of crocodilians has not been well characterized, but there are several reports that describe the antimicrobial efficacy of alligator serum towards bacteria, viruses, and amoeba [4-6].
The crocodile's immune system is much more powerful than that of humans, preventing life-threatening infections after savage territorial fights which often leave the animals with gaping wounds and missing limbs.
"The viruses they can get can be transmitted and that's part of why we do these check-ups, but they can also get bacterial infections and external and internal parasites." She said the primary reason captive crocodiles got sick was stress, but thankfully it was relatively easy to overcome.
Finally, while crocodiles don't age biologically, they are still susceptible to the effects of old age. As they age, they begin to lose their teeth. Without their teeth, they are unable to hunt and eat. This eventually leads to them dying.
The emetic (vomiting) reflex in a crocodilian, Crocodylus porosus, was characterised for the first time using the plant alkaloid veratrine (5 mg kg(-)(1) i.v. or i.p.) as an emetic stimulus. The latency to the onset of vomiting was 8.0+/-0.9 min (mean +/- s.e.m., N=5 animals).
“Ostriches have the most powerful immune system of any land animal,” Ms. Anikeyeva said.
It is said that ostriches have the strongest immune system of any animal in the world. Because of this, they have shown great promise in preventative healthcare in humans and the beauty industry.
"If they've got hold of you, poking the eyes is the only possible way you can fight back - they have thousands of years of instinct telling them this is the only vulnerable part of their body and they need to let go," Mr Cooper says.
Crocodiles also seem to have amazing healing powers. Male crocodiles are fiercely territorial and prone to fighting other males for their territory. It was noticed that despite crocodiles coming away from a fight with scratches and bruises, and sometimes missing limbs, they healed quickly and without infection.
In rare cases, individual crocodilians have been known to bond so strongly with people that they become playmates for years. For example, a man who rescued a crocodile that had been shot in the head became close friends with the animal.
Siamese crocodiles are extremely aggressive and would often fight and wound one another. Surprisingly, despite living in water that's teeming with bacteria, crocodile wounds rarely get infected and heal relatively quickly.
There are two main reasons. First, crocodiles can live for a very long time without food. Second, they lived in places that were the least affected when the asteroid hit Earth.
It may be tempting to think of these big reptiles as totally alien to us humans, but the truth is they live a lot like you do: they grow up quickly, reach full size, gradually get older and weaker, and eventually die (after what was hopefully a long – but not endless – life).
Animals can eat raw meat because they have have stronger stomach acid that helps digest their food. From an evolutionary standpoint, the acid has needed to be much stronger to kill parasites and different bacteria. Why else can't we eat raw meat? It's because that we don't eat our meat right away.
Cheetahs are categorized as vulnerable species, partly because they have been considered to be prone to diseases due to their supposed weak immune system.
The porcine immune system resembles humans in > 80% in contrast to mice with only 10% (Dawson 2011).
Sharks are known for their natural resistance to diseases and viruses despite their primitive immune systems. One article even reports that sharks are immune to all viruses! Doctor Zasloff realized that squalamine is an important contributing factor to sharks' effective immune systems.
It has puzzled researchers for years: Why don't sharks get sick as often as other species? Shark tissue appears to have anticoagulant and antibacterial properties.
Armadillo 'armour' – composed of bony plates known as osteoderms – has been seen to deflect bullets. In one incident, a Texan man was hit in the face when his own bullet bounced back from an armadillo that he tried to shoot. In another, a bullet ricocheting off an armadillo penetrated a house, injuring an elderly lady.
The mayfly has the shortest lifespan of any animal in the world.
The vomiting (emetic) reflex is documented in numerous mammalian species, including primates and carnivores, yet laboratory rats and mice appear to lack this response.
That's right: Squirrels, mice, rats, gophers, beavers and all other rodents are incapable of throwing up. Scientists have long known that rodents aren't able to vomit, but the reason behind it has only more recently been understood, according to Smithsonian(Opens in a new window).
Reptiles, like birds, can get drunk. However, there is not even anecdotal evidence that reptiles seek out and consume alcohol. These lizards were not in it for the beer. It was all about the can.