10 Science Facts That Totally Took Us By Surprise

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Vote up the science facts that make your jaw drop.

Science is full of wonders - new and exciting things that constantly amaze us each day. Science is also jam-packed with unusual and disturbing facts that can throw us off guard. Then there are scientific revelations that astonish us in unexpected ways - and we're left not really sure what to take away from them. 

These science facts are in that last category. They're kind of creepy and not very wholesome - frankly, we're not sure we can whip them out at a dinner party to prove how smart we are. Across the board, these details made our jaws drop (some of them made us blush, too) and completely took us by surprise. How about you?

  • Female Spotted Hyenas Have Functional Penises
    Photo: safaritravelplus / Wikimedia Commons / Public domain
    90 VOTES

    Female Spotted Hyenas Have Functional Penises

    Many animal species have both male and female sex organs, but female spotted hyenas have a pseudo-penis that makes it almost impossible to tell the sexes apart (the same is true for elephants, according to biologist Carin Bondar). Female spotted hyenas are distinct, however, as they are "the only extant mammal that mates and gives birth through a pendulous penis-like clitoris."

    Female spotted hyenas urinate through their pseudo-penises as well as give birth through them. As the dominant members of hyena clans, females depend on these organs to give signals to others. Alongside using a pseudo-penis in sexual activities, female spotted hyenas may determine social and hierarchal relationships with other females via erections.

    90 votes
  • Flatworms Fence Their Mates For Fatherhood Rights
    Photo: Nico Michiels / Wikimedia Commons / CC BY-SA 2.5
    57 VOTES

    Flatworms Fence Their Mates For Fatherhood Rights

    Numerous species of flatworms take part in what can be (and often is) described as "penis fencing." Mating for a flatworm is fierce, but the idea of fighting to fertilize isn't two males exchanging blows for a female. Rather, because flatworms are hermaphroditic, when they face off, it's actually a competition for fatherhood, so to speak.

    The two worms wrestle and try to stab each other with their respective phalluses. The "winner" injects the "loser" with sperm, ultimately fertilizing its eggs through a puncture wound. In some flatworm species, the inseminated flatworm can suck the sperm out, but the sperm itself is barbed and difficult to extract.

    Some species of flatworms find an alternative to mating when no potential mate is around. When given no other option, the Macrostomum hystrix self-fertilize by inserting their penis into their own head and ejaculating.

    57 votes
  • Cockroaches are resilient insects - so much so that in the mid-1960s, the National Committee for a Sane Nuclear Policy ran an advertisement that claimed:

    A nuclear war, if it comes, will not be won by the Americans... the Russians... the Chinese. The winner of World War III will be the cockroach. 

    While cockroaches may not take over the world, they do have bodily systems that allow them to literally lose their heads and keep on living. An open circulatory system allows for less vascular pressure, according to scientist Joseph Kunkel, which means they don't bleed like humans. They are also cold-blooded and require less food; their brains don't control breathing; and they don't need blood to transport oxygen through their bodies.

    A cockroach can live without a head in a lab setting for weeks. Outside of a controlled environment, it's not entirely clear how long the insect would last. 

    74 votes
  • 4
    70 VOTES

    Turtles Can Breathe Through Their Butts

    Turtles are cold-blooded creatures and necessarily hibernate through cold times of the year. They spend long periods in water retracted into their shells, able to survive through low metabolisms and cloacal respiration

    Because a turtle's body temperature is determined by its surroundings, cold temperatures cause its metabolism to slow as the world around it becomes more frigid. The reptiles need less oxygen, but because they're underwater, they aren't able to use their lungs. This is when their butts start doing the breathing for them. 

    Turtles have what's called a cloaca toward their hind ends. This tissue chamber is full of blood vessels that take in oxygen from the surrounding water. As a result, turtles can get the oxygen they need to survive.

    70 votes
  • Malaria Used To Be A Treatment For Syphilis
    Photo: WPA photographer / Wikimedia Commons / Public domain
    61 VOTES

    Malaria Used To Be A Treatment For Syphilis

    Decades ago, fever therapy was used to treat neurosyphilis - the spread of the Treponema pallidum bacteria to the central nervous system. Often the result of years of untreated syphilis, neurosyphilis can cause headaches, vision and hearing loss, paralysis, and dementia, among other symptoms

    Inducing a fever was a form of pyrotherapy - essentially raising one's body temperature to treat a disease. In 1917, Austrian physician Julius Wagner Jauregg experimented with malaria as a way of bringing on fever to treat syphilis; he determined that malaria, above any other fever-inducing infections, was the most effective.

    The risks associated with malaria were deemed less substantive than those of syphilis, and the technique continued into the 1950s

    61 votes
  • 6
    60 VOTES

    Gray Whales Often Reproduce Via Threesomes

    To engage in sex, male gray whales often require a female (obviously) and a second male.

    The coming together of three whales for mating features two males signaling to a female. Once the group gets close, they roll and rub to familiarize "themselves with one another and make sure the female is receptive to mating."

    As the males take turns with the female, one mates while the other serves as a prop to keep the copulating pair together. 

    60 votes