This article was published in Scientific American’s former blog network and reflects the views of the author, not necessarily those of Scientific American
February is the month of love, and with Valentine’s Day behind us, it is only natural to feel a certain affection for those that were sadly alone on this year’s February the 14th.
That is why this post is devoted to the outcasts on the animal kingdom, the species that sadly do not get as much love and adoration as the more fuzzy or "cute" animals do, such as chimpanzees, tigers and polar bears.
Whether it is because of their appearance, unfriendly demeanor, or unsanitary reputation, these animals still have something to share. It is like the child’s author Dr. Seuss wrote in his book Horton Hears a Who, "A person’s a person, no matter how small." I happen to think that every animal is amazing in their own way, no matter what their outward appearance or behavior.
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In this post, five fascinating animals will be discussed, and while you may not burst with affection, maybe that next time you see them scurrying by your feet or through the cage at the zoo, you will give them pause. After all, evolution designed them to be the best at what they do, not for a fashion show.
Aye-Aye
In anyone’s book, the Aye-Aye is not a pretty animal.
This primate relative can be found in Madagascar, and with its big eyes, large ears and long but slender fingers, resembles something more commonly found in a horror movie. But, like all the animals on this list, there is always something to admire.
The Aye-aye is a nocturnal creature, and uses a unique method to feed, akin to that of a woodpecker. It uses its long middle finger to tap on trees and locate insect larvae underneath the bark using its impressive hearing. Then, using its rodent-like teeth, the aye-aye bores a hole in the bark and uses its long middle finger to fish them out.
The only way to truly understand how this incredible feat is achieved is to actually see it. You can watch a video of an Aye-Aye eating, courtesy of Arkive.org, here.
Cockroaches
The lowly cockroach is almost universally despised, hated and feared. I can think of no other animal (other than perhaps the rat) that elicits such a strong reaction from people from just the mention of it!
But, it does deserve some respect for holding that title as long as it has. It is a wonder of evolution, and has earned every penny of that reputation.
The cockroach has remained almost unchanged for over 300 million years, is adept at spreading disease, leaves trails of fecal matter wherever it goes, reproduces quickly, and can survive on almost anything. It is the ultimate generalist.
They can emerge alive after being completely submerged for over 20 minutes in water, endure well past the lethal dose of radiation for a human, and most impressively, survive for over a week after getting its head chopped off.
Their survival is due to the fact that much of their nervous system activity takes place within neural ganglia throughout their body, and they breath through holes (or spiracles) in their abdomen. Cockroaches can even survive a long time without food, so why does it die after a whole week?
Simple: It dies of thirst.
As disgusting and repulsive as cockroaches are, you much admit, they are an impressive evolutionary feat. However, that doesn’t mean I want them in my house!
Naked Mole Rats
One of the first things you must know about naked mole rats, Heterocephalus glaber, is that they have no hair (hence the naked moniker), have wrinkled pink skin and very large incisors used to construct tunnels underground. They are also almost completely blind, have a lifespan of up to 30 years and live in a society similar to that of bees and wasps.
This type of social structure is known as eusociality, and is common in insect colonies, but is only present in two mammalian species – the naked and Damaraland mole rats.
In a naked mole rat colony, there is only one breeding queen and a few breeding males at a time, with others temporarily inhibited from reproduction by special chemical signals produced by the queen. The colonies consist of hundreds of workers (who scavenge for food and protect the colony) and non-workers (whose sole job is servicing the queen).
Like other eusocial insects, workers will protect the colony at any cost in a display of altruism (self-sacrifice). If a snake attacks the colony and cannot be deterred, a worker will sacrifice him or herself to be eaten by the snake in order to ensure the colonies continued survival. That way, despite the death of the individual, part of their genetic legacy can be carried on through future offspring. This is similar to a worker bee stinging a badger and killing itself to protect the hive.
Not only do naked mole rats show altruistic behavior for their genetically related brothers and sisters, but they also have potential to help in the medical research field.
In a 2009 study, scientists discovered that naked mole rats do not contract cancer. This is due to the p16 and p27 genes, which control cell crowding. Unlike other mammals, whose cells continue to grow until they overlap upon one another, these genes inhibit that. In fact, cells stop growing as soon as they touch another, leading to the prevention of the uncontrolled cellular proliferation that leads to tumor growth.
Not bad for an animal that looks like it crawled out of John Hurt’s abdomen in the move Alien.
Vultures
Vultures are carrion eaters, meaning they eat the carcasses of dead animals long after any other predator would give it a look. Add in their huge wingspan, no feathers on their head and neck, sharp talons and beak, you get an animal that is not going to win any popularity contests. And yet, they are absolutely fascinating animals if you give them a chance. While this may not convert you into becoming their biggest fans, perhaps it will give you a new appreciation for these underappreciated avians.
There are two groups of vultures: Old World and New World. But, they are not closely related. In fact, the similarities they share are only due to convergent evolution – similar traits evolving in two completely separate groups of species. Old World vultures, which include buzzards and hawks, are found in Africa and Europe, and use sight to find their prey. In contrast, the New World vultures (including Condors) are found in the America’s and utilize a keen sense of smell to find prey.
Aside from giving the vultures their distinct look, the bald head and long neck are actual superb adaptations to its diet of dead animals, allowing them to plunge their heads into carcasses and come out smelling like a rose (or at least a carrion flower).
If other birds stuck their heads into dead animals, they would emerge with their feathers bent and covered in flesh and blood, which could lead to disease. Luckily, vultures don’t have that problem, and they can digest meat at practically any stage of decay. They are nature’s garbage men, eating that which no one else would. In fact, their stomach acid is so strong that it can digest meat infected with botulism, cholera and even anthrax with no ill effects!
Surprisingly, despite their vile reputation, vultures are actually very clean animals. Their urine contains such strong chemicals, that they use it to disinfect their legs after walking around on dead and potentially diseased carcasses.
How can you not be impressed with an animal that takes such pride in its health?
Deep-sea Anglerfish
If the Aye-Aye looks like something out of a horror movie, than the deep-sea anglerfish can only be found in the darkest of nightmares. Which, conveniently, is precisely where it lives, in the darkest depths of the ocean, where there is no natural light.
The female anglerfish, with its huge crescent jaw filled to the brim with teeth, possesses a remarkable appendage that grows out of its back and stretches over its head – a bioluminescent sac that functions like a fishing lure. This light attracts fish into the angler’s gaping maw, which itself is worthy of its position on this list.
And yet, something even more incredible and disturbing awaited scientists attempting to unravel the anglerfish’s mating practices. The problem was, they never found a male. So, how did they reproduce?
The key was the female itself.
Scientists discovered numerous parasite-like growths on the female, which when dissected, contained male gonads. Basically, the vestigial remains of a former male anglerfish.
Eventually, it was discovered that male anglerfish do exist, but are much smaller and most likely do not feed. Their entire lives are spent searching for a female, using their highly advanced olfactory senses to find her pheromone trail.
Once found, the male bites the female and releases an enzyme that permanently fuses his mouthparts to her skin. Over time, he is slowly degraded into nothing more than a gonadal sac, ready to be used by the female when she is ready to spawn.
There are plenty more animals that boast strange and interesting qualities that deserve to be recognized, such as the pangolin, aardvark, platypus, echidna, and more! It’s all just a matter of perspective on what is appealing, and looking beyond that to find the amazingness below.
Text References:
1) How Stuff Works - Cockroaches
3) Smithsonian – Naked Mole Rats and ScienceNOW – Naked Mole Rat Wins War on Cancer
4) Vultures of the World – Vultures and MadSci.org – Vulture Digestion
5) National Geographic - Anglerfish
Image Credits: 1) Photo of Cockroach posted to Wikimedia Commons by Wm Jas (Creative Commons license). 2) Photo of Aye-aye (Daubentonia madagascariensis) posted to Wikimedia Commons by Tom Junek (Creative Commons license). 3) Photo of Naked Mole Rat (Heterocephalus glaber) posted to Wikimedia Commons by Trisha M Shears (Creative Commons license). 4) Picture of Deep-sea Anglerfish posted to Wikimedia Commons from plate 117 of Oceanic Ichthyology by G. Brown Goode and Tarleton H. Bean, published in 1896. (Public Domain license). 5) Photo of Griffon Vulture, taken by David Manly at the Amsterdam Zoo.
About the Author: David Manly is a Canadian freelance science journalist, who holds degrees in Biology and Zoology, as well as a Masters of Journalism. He has worked with dozens of animals as a scientist, and now spends time writing about the wondrous world of animals for Lab Spaces, as well as for his own blog The Definitive Host, and you can always find him on Twitter. He has a passion for all animals, regardless of reputation. When he’s not writing, you can find him reading a book that usually has something to do with science or re-watching one of the countless animal documentaries that he owns.
The views expressed are those of the author and are not necessarily those of Scientific American.