10 Fascinating Cases Of Animal Gigantism

10Flores Giant Rat

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Humans are easily frightened by the tiniest animals: Cockroaches, spiders, and mice seem specifically designed to scare the bejeezus out of us. Some grown men would even prefer to wrestle a bear or take on a pack of coyotes than let a mouse run up the leg of their pants.
These men should probably avoid the island of Flores, Indonesia. It’s home to the Flores Giant Rat, which has the single virtue of being too large to fit up your pants leg. This isn’t the kind of rodent to be restrained by mouse traps: its body can reach 45 centimeters (18 in) in length, and that’s before you add its 75-centimeter (30 in) tail. Then the rat can exceed 1.2 meters (4 ft).
This really is the stuff of nightmares, but at least most of us are physically big enough to fight off a giant rat.  Unfortunately, the rats wouldn’t have been so easy to shrug off for our ancestors: Homo floresiensis, who shared Flores Island with them around 12,000 years ago. At around 1 meter (3 ft) tall, these early humans would have come face to face with rats frighteningly close to them in size.
Luckily for the H. floresiensis community, Flores giant rats are believed to be vegetarians.

9Nuralagus

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The Nuralagus rex was a type of prehistoric rabbit, which developed into a giant due to its predator-free habitat on the Mediterranean island of Minorca. The largest specimens could have weighed around 22 kilograms (50 lbs), which is outrageous when you compare it to the 1.8 kilograms (4 lbs) of the largest modern rabbits.
The tiny skull of the otherwise-giant rabbit suggests that its capacities for sight and hearing were significantly impaired compared to those of normal rabbits. This is most likely another result of the lack of predators on the island. With nothing around to kill it, there was no need to develop or maintain the traits necessary for competition and survival. As you can imagine, the extraordinary size of the nuralagus meant that it didn’t exactlyhop around the island. It instead plodded quite slowly, more like a sloth than a rabbit.

8Solomon Islands Skink

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The Solomon Islands skink is unusual in many ways apart from the fact that it can reach nearly 75 centimeters (30 in) in length—three times larger than the average skink size. Unlike most reptiles, which usually produce offspring by laying eggs, the female Solomon Islands skink carries its young internally. When the baby skinks are born, they are sometimes already half the size of their mother.
The giant skinks are sometimes referred to as “monkey-tailed skinks” because their tails have the unusual ability to grasp the branches of trees. But this ability comes at a price: The Solomon Islands skink is one of the few lizards unable to detach its tail at the approach of a predator. Lacking this advantage, it will often hiss and bite to defend itself.

7Chappell Island Tiger Snake

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At 2.4 meters (8 ft) in length, the Chappell Island tiger snake is the largest of all tiger snakes. For centuries, it has shared Mount Chappell Island, Australia, with a large number of local muttonbirds and absolutely no serious predators. Since it’s the only type of snake found on the island, it essentially has a monopoly over the muttonbird chicks, which it devours with relish every breeding season. The snake can eat so many hapless chicks in one six-week period that it often spends the rest of the year digesting its victims.
Like many Australian snakes, the Chappell Island tiger snake is highly venomous, and its bite can be lethal to any human foolish enough to interfere in the muttonbird business.

6Madagascar Giant Pill-Millipede

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The giant pill-millipede of Madagascar is known by scientists asSphaerotheriida, but locals have dubbed it more accurately as “star poo.” Though they look like normal millipedes in their relaxed state, they have the ability to roll themselves into an armored ball at the first sign of danger. Once they retreat into their armored plates, almost nothing can force them to unroll against their will.
The largest pill-millipedes can reach the size of a baseball. Unlike centipedes but like other millipedes, the giant pill-millipedes are non-venomous, and they live on a diet of decaying plant matter.

5Saint Helena Giant Earwig

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“Absolutely horrifying” is probably a reasonable description of the Saint Helena earwig, which can reach nearly 10 centimeters (4 in) in length. First discovered in 1798, the giant earwig has been inhabiting nightmares ever since.
The folk belief that earwigs are capable of crawling into human ears and eating brains is now well-known as a myth, but if you still harbor any fears, then rest assured: The Saint Helena earwig is actually too enormous to even fit in your ear.
Believe it or not, the hideous exterior of the Saint Helena earwig actually conceals a warm, loving, and tender interior. The giant species is renowned among earwig researchers for its unusually advanced levels of maternal care. After the eggs have been laid, the mother frequently cleans them to protect them from fungi and is known to defend them from predators.
The giant earwigs, like Napoleon in his later years, are endemic to the tiny Atlantic island of Saint Helena. There have been no sightings since about 1967, leading many to believe that extinction may have occurred as a result of predation from the introduced centipede.

4The Dodo

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The dodo—a kind of gigantic, flightless pigeon—is not quite so terrifying as other entries in this list. But dodos are a still a very good example of island gigantism at work. Isolated for thousands of years on the small Indian Ocean island of Mauritius and completely lacking any major predators, dodos were completely fearless of humans.
The story of human contact with dodos is a famous one. When Dutch sailors arrived in the 16th century, they found the large, plump, overfed birds rather laughable. Despite the meek, trusting nature of the dodos, they were routinely butchered for food by humans, and their flightlessness made themeasy prey for even the laziest of introduced predators.
This slaughter, coupled with the fact that the dodos couldn’t reverse the evolutionary trend of thousands of years in a matter of decades, led to the species being exterminated by the end of the 17th century.

3Galapagos Islands Giant Tortoise

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The giant tortoises of the Galapagos Islands off the coast of Ecuador have the potential to outlive any other vertebrate. They can routinely live for over 100 years, and one of them held on until the ripe age of 152. They’re also true giants of the tortoise world: Some subspecies can reach 250 kilograms (550 lbs) and over 1.5 meters (5 ft) in length.
At the time of Charles Darwin’s famous visit, there were 14 different subspecies of giant tortoise in the Galapagos Islands. Each kind of tortoise originated from a single ancestor, but their evolution began to diverge after they found themselves on different islands with different challenges and began to evolve accordingly.
Giant tortoises display a fascinating form of symbiotic behavior when it comes to ridding themselves of parasites such as ticks. Whenever they’re in need of pest removal, they stretch up on their hind legs, allowing passing birds to peck away all the ticks.
The number of subspecies has now dwindled to 10 after centuries of hunting, poaching, and the introduction of domestic animals. Taken together, these things probably killed more than 100,000 giant tortoises. But thanks to the increased efforts of conservationists, only 120 of the 15,000-strong population have been killed by poachers since 1990.

2Giant Fijian Long-Horned Beetle

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The giant Fijian long-horned beetle is the second-largest beetle in the world, reaching an extraordinary body length (by beetle standards) of 15 centimeters (7 in). The beetle lives a simple life in the trees of Fiji on a diet of plant matter, but anyone who is generally creeped out by insects will still find cause to be uneasy: The horns which give the beetle its name can also reach lengths of more than 12 centimeters (6 in), meaning that its horns are often nearly as long as its gigantic body.
The larvae take 12 years to reach their full adult size. Many of them don’t survive that vulnerable period, since the larvae are sought out as a rare delicacy by Fijian villagers. Several tribes consider them to be sacred, and only the village high chief is permitted to eat them.
But the few long-horned beetles which make it into adulthood become truly fearsome: “Powerful jaws” and “very loud whirring noise when flying” are just some of the phrases insectophobes don’t like to hear. Upon being disturbed, the beetles will also respond with an alarming hissing noise.

1Elephant Bird

Christie's specialist James Hyslop holds a chicken egg next to a pre-17th century, sub-fossilised Elephant Bird egg in London
The aptly named elephant birds of Madagascar were around 3 meters (10 ft) tall and could weigh 400 kilograms (900 lbs). If you have ever seen an emu or ostrich and been amazed by its size, then you’ll understand how early visitors to Madagascar must have felt when they caught sight of these creatures before the species died off in the late 17th century.
Elephant birds were probably the largest birds ever to have lived. Even their eggs were a full meter (3 ft) in circumference, and their fearsome appearance gave rise to the legendary “Roc” of Arabian folk tales. This fabled creature was thought to consume elephants, but such a rumor says more about the effect of the elephant birds on travelers’ imaginations than their actual feeding habits.
The real elephant bird was more heavily built than the more familiar moa of New Zealand, and its eggs were even larger.

Top 10 Greatest Mathematicians

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Pythagoras of Samos
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Greek Mathematician Pythagoras is considered by some to be one of the first great mathematicians. Living around 570 to 495 BC, in modern day Greece, he is known to have founded the Pythagorean cult, who were noted by Aristotle to be one of the first groups to actively study and advance mathematics. He is also commonly credited with the Pythagorean Theorem within trigonometry. However, some sources doubt that is was him who constructed the proof (Some attribute it to his students, or Baudhayana, who lived some 300 years earlier in India). Nonetheless, the effect of such, as with large portions of fundamental mathematics, is commonly felt today, with the theorem playing a large part in modern measurements and technological equipment, as well as being the base of a large portion of other areas and theorems in mathematics. But, unlike most ancient theories, it played a bearing on the development of geometry, as well as opening the door to the study of mathematics as a worthwhile endeavor. Thus, he could be called the founding father of modern mathematics.
9
Andrew Wiles
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The only currently living mathematician on this list, Andrew Wiles is most well known for his proof of Fermat’s Last Theorem: That no positive integers, a, b and c can satisfy the equation a^n+b^n=c^n For n greater then 2. (If n=2 it is the Pythagoras Formula). Although the contributions to math are not, perhaps, as grand as other on this list, he did ‘invent’ large portions of new mathematics for his proof of the theorem. Besides, his dedication is often admired by most, as he quite literally shut himself away for 7 years to formulate a solution. When it was found that the solution contained an error, he returned to solitude for a further year before the solution was accepted. To put in perspective how ground breaking and new the math was, it had been said that you could count the number of mathematicians in the world on one hand who, at the time, could understand and validate his proof. Nonetheless, the effects of such are likely to only increase as time passes (and more and more people can understand it).
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Isaac Newton and Wilhelm Leibniz
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I have placed these two together as they are both often given the honor of being the ‘inventor’ of modern infinitesimal calculus, and as such have both made monolithic contributions to the field. To start, Leibniz is often given the credit for introducing modern standard notation, notably the integral sign. He made large contributions to the field of Topology. Whereas all round genius Isaac Newton has, because of the grand scientific epic Principia, generally become the primary man hailed by most to be the actual inventor of calculus. Nonetheless, what can be said is that both men made considerable vast contributions in their own manner.
7
Leonardo Pisano Blgollo
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Blgollo, also known as Leonardo Fibonacci, is perhaps one of the middle ages greatest mathematicians. Living from 1170 to 1250, he is best known for introducing the infamous Fibonacci Series to the western world. Although known to Indian mathematicians since approximately 200 BC, it was, nonetheless, a truly insightful sequence, appearing in biological systems frequently. In addition, from this Fibonacci also contributed greatly to the introduction of the Arabic numbering system. Something he is often forgotten for.
Haven spent a large portion of his childhood within North Africa he learned the Arabic numbering system, and upon realizing it was far simpler and more efficient then the bulky Roman numerals, decided to travel the Arab world learning from the leading mathematicians of the day. Upon returning to Italy in 1202, he published his Liber Abaci, whereupon the Arabic numbers were introduced and applied to many world situations to further advocate their use. As a result of his work the system was gradually adopted and today he is considered a major player in the development of modern mathematics.
6
Alan Turing
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Computer Scientist and Cryptanalyst Alan Turing is regarded my many, if not most, to be one of the greatest minds of the 20th Century. Having worked in the Government Code and Cypher School in Britain during the second world war, he made significant discoveries and created ground breaking methods of code breaking that would eventually aid in cracking the German Enigma Encryptions. Undoubtedly affecting the outcome of the war, or at least the time-scale.
After the end of the war he invested his time in computing. Having come up with idea of a computing style machine before the war, he is considered one of the first true computer scientists. Furthermore, he wrote a range of brilliant papers on the subject of computing that are still relevant today, notably on Artificial Intelligence, on which he developed the Turing test which is still used to evaluate a computers ‘intelligence’. Remarkably, he began in 1948 working with D. G. Champernowne, an undergraduate acquaintance on a computer chess program for a machine not yet in existence. He would play the ‘part’ of the machine in testing such programs.
5
René Descartes
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French Philosopher, Physicist and Mathematician Rene Descartes is best known for his ‘Cogito Ergo Sum’ philosophy. Despite this, the Frenchman, who lived 1596 to 1650, made ground breaking contributions to mathematics. Alongside Newton and Leibniz, Descartes helped provide the foundations of modern calculus (which Newton and Leibniz later built upon), which in itself had great bearing on the modern day field. Alongside this, and perhaps more familiar to the reader, is his development of Cartesian Geometry, known to most as the standard graph (Square grid lines, x and y axis, etc.) and its use of algebra to describe the various locations on such. Before this most geometers used plain paper (or another material or surface) to preform their art. Previously, such distances had to be measured literally, or scaled. With the introduction of Cartesian Geometry this changed dramatically, points could now be expressed as points on a graph, and as such, graphs could be drawn to any scale, also these points did not necessarily have to be numbers. The final contribution to the field was his introduction of superscripts within algebra to express powers. And thus, like many others in this list, contributed to the development of modern mathematical notation.
4
Euclid
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Living around 300BC, he is considered the Father of Geometry and his magnum opus: Elements, is one the greatest mathematical works in history, with its being in use in education up until the 20th century. Unfortunately, very little is known about his life, and what exists was written long after his presumed death. Nonetheless, Euclid is credited with the instruction of the rigorous, logical proof for theorems and conjectures. Such a framework is still used to this day, and thus, arguably, he has had the greatest influence of all mathematicians on this list. Alongside his Elements were five other surviving works, thought to have been written by him, all generally on the topic of Geometry or Number theory. There are also another five works that have, sadly, been lost throughout history.
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G. F. Bernhard Riemann
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Bernhard Riemann, born to a poor family in 1826, would rise to become one of the worlds prominent mathematicians in the 19th Century. The list of contributions to geometry are large, and he has a wide range of theorems bearing his name. To name just a few: Riemannian Geometry, Riemannian Surfaces and the Riemann Integral. However, he is perhaps most famous (or infamous) for his legendarily difficult Riemann Hypothesis; an extremely complex problem on the matter of the distributions of prime numbers. Largely ignored for the first 50 years following its appearance, due to few other mathematicians actually understanding his work at the time, it has quickly risen to become one of the greatest open questions in modern science, baffling and confounding even the greatest mathematicians. Although progress has been made, its has been incredibly slow. However, a prize of $1 million has been offered from the Clay Maths Institute for a proof, and one would almost undoubtedly receive a Fields medal if under 40 (The Nobel prize of mathematics). The fallout from such a proof is hypothesized to be large: Major encryption systems are thought to be breakable with such a proof, and all that rely on them would collapse. As well as this, a proof of the hypothesis is expected to use ‘new mathematics’. It would seem that, even in death, Riemann’s work may still pave the way for new contributions to the field, just as he did in life.
2
Carl Friedrich Gauss
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Child prodigy Gauss, the ‘Prince of Mathematics’, made his first major discovery whilst still a teenager, and wrote the incredible Disquisitiones Arithmeticae, his magnum opus, by the time he was 21. Many know Gauss for his outstanding mental ability – quoted to have added the numbers 1 to 100 within seconds whilst attending primary school (with the aid of a clever trick). The local Duke, recognizing his talent, sent him to Collegium Carolinum before he left for Gottingen (at the time it was the most prestigious mathematical university in the world, with many of the best attending). After graduating in 1798 (at the age of 22), he began to make several important contributions in major areas of mathematics, most notably number theory (especially on Prime numbers). He went on to prove the fundamental theorem of algebra, and introduced the Gaussian gravitational constant in physics, as well as much more – all this before he was 24! Needless to say, he continued his work up until his death at the age of 77, and had made major advances in the field which have echoed down through time.
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Leonhard Euler
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If Gauss is the Prince, Euler is the King. Living from 1707 to 1783, he is regarded as the greatest mathematician to have ever walked this planet. It is said that all mathematical formulas are named after the next person after Euler to discover them. In his day he was ground breaking and on par with Einstein in genius. His primary (if that’s possible) contribution to the field is with the introduction of mathematical notation including the concept of a function (and how it is written as f(x)), shorthand trigonometric functions, the ‘e’ for the base of the natural logarithm (The Euler Constant), the Greek letter Sigma for summation and the letter ‘/i’ for imaginary units, as well as the symbol pi for the ratio of a circles circumference to its diameter. All of which play a huge bearing on modern mathematics, from the every day to the incredibly complex.
As well as this, he also solved the Seven Bridges of Koenigsberg problem in graph theory, found the Euler Characteristic for connecting the number of vertices, edges and faces of an object, and (dis)proved many well known theories, too many to list. Furthermore, he continued to develop calculus, topology, number theory, analysis and graph theory as well as much, much more – and ultimately he paved the way for modern mathematics and all its revelations. It is probably no coincidence that industry and technological developments rapidly increased around this time

10 Things You Never Knew About The Biology Of Sex


10Arousal And Disgust

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Sex is an innately disgusting thing. Copious body fluids aside, the mere act of sex is something we would never do if pleasure wasn’t involved. That may be one of the reasons arousal actually inhibits feelings of disgust.
“Disgust-induced avoidance” is the scientific term for not wanting to do something gross, like hesitating to drink a glass of water with a large fly floating in it. Normally, you wouldn’t even think about it. When you’re aroused, though, it’s more likely that you won’t care and take a big gulp anyway. In a recent study, 90 women were split into three groups: aroused, unaroused, and neutral. Then they were given 16 different tasks that ranged from “disgusting” to “more disgusting”—wiping their hands with a used tissue, reaching into a bucket of used condoms, and yes, drinking from a glass with a dead bug in it.
In reality, the bug was fake, and the condoms weren’t actually used—but the participants didn’t know that. The aroused women were overwhelmingly more likely to follow through with the tasks than any of the other groups, especially if the “disgusting” task was sexual in nature, like the condom bucket or putting lubrication on a vibrator. This suggests that inhibiting disgust is an important part of making people actually want to have sex.

9Transient Global Amnesia

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Transient global amnesia is a condition in which a person’s memory randomly disappears for a short amount of time. It happens suddenly and usually it goes away after only a few hours—but during that time, you can’t remember anything past a certain point. It also affects your ability to make new memories, so you’re constantly living inside a window of just a few seconds between doing something and forgetting about it. It’s like Memento, but without all the tattoos.
Since it’s so rare—only about three people out of 100,000 get it every year—doctors don’t really know what causes it, but one similarity has been popping up regularly since it was first recorded in 1956. In most cases, the person was having sex right before their memory goes blank.
Beyond the inability to remember anything, there aren’t any other side effects to transient global amnesia, but that doesn’t make it any less frightening. In a case from 1964, a man had an orgasm, then immediately shouted, “Where am I?” In reports where the person wasn’t having sex at the time of the attack, the trigger was usually something similar—strenuous activity of some sort, or a sudden change in body temperature.

8Hot Women And Health

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When you do something dangerous, like skydiving, your body pumps out massively increased levels of a stress hormone called cortisol. Cortisol is the primary hormone in the “fight or flight” response that floods your system with adrenaline and primes your body for survival. Put an attractive woman in a room with a man, however, and that man’s body suddenly can’t tell the difference between a nice set of legs and a rampaging bear.
In fact, just being alone with a beautiful woman for five minutes raises cortisol nearly to heart attack levels. It sounds like something you’d see in an old Tom & Jerry cartoon, but when Spanish researchers tested male hormone levels with a saliva swab after solo contact with an attractive female, their cortisol was actually right around the levels you’d expect to see after skydiving. The more attractive he thought the female was, the higher his cortisol levels rose.
They came to the conclusion that, like fighting off a predator, sexual interest is seen at the hormonal level as a challenge to be overcome. The more dangerous (attractive) the predator (woman), the more prepared he needs to be to survive (get laid). But there’s a catch-22: Women are actually turned offby men with higher stress levels. Sorry, guys. You just can’t win.

7Orgasmic Exercise

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Getting to the gym is hard for a lot of people. It’s a commitment, and one that comes at the expense of other, more enjoyable things—like virtually anything else. But for 5 percent of women, there might be a new reason to start working out: exercise-induced orgasms. It’s exactly what it sounds like—women have reported reaching climax simply from working out. The phenomenon was first mentioned in 1953 during an unrelated sex study by Dr. Alfred Kinsey, who said that a small percentage of the 6,000 women he interviewed voluntarily mentioned that sometimes their workouts came with some extra motivation.
A more recent study found that closer to 15 percent of women have experienced the phenomenon, and twice as many get at least some kind sexual pleasure. Granted, the “study” was an online survey without a whole lot of scientific control, but it does seem to be a fairly widespread issue. There’s even a name for it—”coregasm,” since most of the time, it’s triggered by abdominal exercises. It’s female-exclusive, as far as anybody can tell—sorry again, guys.

6Zero-Gravity Sex

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With several planned Mars missions just around the corner—some of which expect to put the astronauts and their families in zero-G conditions for more than 500 days—someone has to come out and ask the question that’s on everybody’s mind: “Can we do it in space?”
The answer is tricky, and NASA has already tackled it several times. As far as they’re willing to admit, nobody’s ever tried it, but the logistics would be something approaching rocket science. One expert put it in terms anybody could understand: “You have no traction and you keep bumping against the walls.” Or as Newton would have said, every thrust has an equal and opposite counter-thrust. Then there’s the problem of biology—sperm has never been asked to perform outside of normal gravity. In microgravity it would just ricochet around the uterus, bouncing off the walls like the kids inEnder’s Game.
Finally, there’s the small matter of what the radiation would do to a fetus if the hurdles of conception were ever overcome. We’re already unsure what the effects of long-term solar radiation would be on an adult, let alone a developing fetus
With several planned Mars missions just around the corner—some of which expect to put the astronauts and their families in zero-G conditions for more than 500 days—someone has to come out and ask the question that’s on everybody’s mind: “Can we do it in space?”
The answer is tricky, and NASA has already tackled it several times. As far as they’re willing to admit, nobody’s ever tried it, but the logistics would be something approaching rocket science. One expert put it in terms anybody could understand: “You have no traction and you keep bumping against the walls.” Or as Newton would have said, every thrust has an equal and opposite counter-thrust. Then there’s the problem of biology—sperm has never been asked to perform outside of normal gravity. In microgravity it would just ricochet around the uterus, bouncing off the walls like the kids inEnder’s Game.
Finally, there’s the small matter of what the radiation would do to a fetus if the hurdles of conception were ever overcome. We’re already unsure what the effects of long-term solar radiation would be on an adult, let alone a developing fetus.

5Boosts Immune System

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When you get a cold, your first reaction probably isn’t to kick yourself for not having more sex. From a physical standpoint, sex is healthy for you—after all, it’s just another form of exercise—but it also benefits you at the cellular level by raising levels of igA, an antibody found in your mucus that kills cold germs. In most cases, igA is a good indicator of immune system health—the more igA you have, the stronger your immune system is.
When a research team tested a group of college students in 1999, they found that people who had sex at least twice a week had higher levels of igA in their system. They came to the conclusion that by regularly exposing themselves to all the various germs other people carry, these people were constantly building an immunity to a range of viruses and bacteria, similar to the waychildren who eat dirt wind up healthier.
On the other hand, the abstinent students who didn’t have that intimate contact had fewer biological defenses because their bodies weren’t getting those tiny bumps of exposure. On a final, freakish third hand, having sex toomuch (three or more times per week) drops those igA numbers right back down to abstinence levels.

4Reduces Risk Of Prostate Cancer

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Maybe going for the gold in the cosmic sexolympics won’t help your immune system, but it may very well reduce your risk of getting prostate cancer. Prostate cancer normally affects men older than 45, with most diagnoses cropping up around the age of 70. In a massive eight-year study that followed 30,000 men, the National Cancer Institute found that men who popped one off at least 21 times per month were one-third less likely to develop prostate cancer than men who averaged four or five monthly deposits. During the course of the study, 1,500 participants came down with prostate cancer, further clarifying the statistics.
Despite the clear results, the researchers weren’t sure why frequent ejaculations had an effect on prostate cancer. One of the main theories is that it keeps the passages open and prevents buildup. As the good folks at Johns Hopkins put it, all that release sort of “cleans house” up in the prostate, washing away fluids and tissue that could become infected or inflamed.

3Sexual Genetics

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Most people picture the Stone Age as a rampaging sex frenzy peppered withraucous interbreeding between Neanderthals and Homo Everythings, the kind from which you wake up three million years later with a pounding headache and an acute sense of regret. While it’s true that Homo sapiens and Neanderthals had some liaisons between the sheets, it didn’t happen nearly as often as we once thought. Spicy or not, the study of ancient sex is giving us something else: clues to the movements of early humanity.
The genetic similarities between Neanderthals, Denisovans, and a recently discovered African ancestor are giving us a better idea of the migration of early humans. The most prevalent theory has long been the “Out of Africa” theory, which states that all modern humans started in Africa, moved east, then migrated north into the Eurasia region.
But based on the Neanderthal genome that was published in 2010 (along with gene testing from people living in various regions in Africa, Asia, and Europe), it’s beginning to look more complicated than that. Early humans may have migrated out of Africa, mixed with Neanderthals, then gone back to Africa carrying a trace of Neanderthal genetics, which then spread and replaced the native genes. To this day, about 4 percent of our genes were inherited from our Neanderthal ancestors.

2High-Pitched Voices

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If you were asked to form a mental image of masculinity, what would you picture? Muscles? Beards? Deep Mufasa-esque voices echoing through the canyons of your own insecurity? According to research, most women feel the same way about what constitutes manliness, and those are the type of men most women look for in a mate. A deep voice is inextricably linked to higher testosterone levels, which is further associated with genetic strength—big men make better baby daddies.
However, this may be one of the few cases of a woman’s body telling her the wrong thing. As it turns out, men with higher-pitched voices pack a more potent punch. A paper published in 2011 found that although deeper-voiced men were considered more attractive, they invariably had lower concentrations of sperm than their less-attractive falsetto counterparts. The reason could be a simple evolutionary trade-off—masculine men have more chances to reproduce, so each try doesn’t necessarily need to be a winner. Men who don’t get that many chances need to throw everything they’ve got into it, because who knows when they’ll get another shot?

1Human Penile Spines

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Penile spines, as you may know, are spines on the penis. Plenty of animals have them, from the humble field mouse to the proud buffy-tufted marmoset. They’re usually used to rake the inner walls of a female’s vagina after sex to induce ovulation or to prevent the female from mating with anyone else. As it turns out, humans have the genetic coding to create penile spines, too—at some point, we had prickly pickles just like everyone else in nature.
So what happened to them? A team of biologists at the Stanford School of Medicine set out to compare the DNA differences between humans and chimpanzees, one of our closest living relatives, and found a very small but very important deviation. While we still have the genes for penile spines, we lost the switch that activates those genes.
You see, DNA is made up of different types of genomes. Protein-coding genes are like factories—they make proteins that are assigned to different roles. Non-coding DNA strands are like light switches—they’re responsible for turning a protein-coding gene on or off at a specific time. In humans, the penile spine protein factory is still there, waiting to be flipped on, but the switch disappeared.
Why? The best guess is that mammals that mate with a lot of partners tend to have more prominent spines, while mammals that practice pair bonding have recessed spines—for example, chimp spines are more like bumps. At some point, it became more advantageous for humans to pair together for longer, and the spine switch was lost along the way. Love is a beautiful thing.