If I asked you what the most common vertebrate on Earth was, how many guesses would it take for you to think of the bristlemouth? I couldn't even tell you how many guesses it would take me. Don't feel bad -- apparently scientists didn't realize the dominance of the bristelmouth until just recently. The mysteries of the deep sometimes follow the rule of "out of sight, out of mind."

Their official name is Gonostomatidae, but they are often called bristlemouths because their teeth look like bristles. First seen in the ocean depths by William Beebe (a deep ocean diver pioneer) in the 1930's, they can be found in the fossil record dating as far back as the Miocene (well over five million years ago). They live in the deep ocean, beyond where sunlight usually penetrates, from depths of half of mile to several miles.

Despite how big and bad they might look, bristlemouths are actually tiny -- about the size of your pinky. But the weirdness of these fish goes way beyond their looks: they are hemaphrodites, born male with the ability to switch their sex to female, they swim funny, and they glow in the dark. Scientists estimate there are TRILLIONS of bristlemouths in the ocean, maybe even quadrillions. That means there could be over 10 of them per square meter.
So next time you're out on the ocean beyond, think about the crazy amount of life that's underneath you (and how much of we don't yet understand!).
Here's some more geek from the week:
- Stanford researchers are studying lovebirds to help them design better drones.
- These snails may be slow, but they are also deadly.
- Artists take on Schrödinger's cat.
- A new creative use for conductive paint: making music. [VIDEO]
- The Smithsonian Institute is collecting frozen vegetables FOR SCIENCE.
- Amazing and moving video made from visualizing UN data on global refugees from 1975 to 2012.
- With this bionic hand we are one step closer to the Six Million Dollar Man becoming a reality.
- Over a hundred years later, Marie Curie's research notebooks and possessions are still radioactive.
- Lose yourself on Mars from the comfort of your own home. [INTERACTIVE]
- The history of how many planets are in our solar system is more complicated than you might think. [INTERACTIVE]
- Explore every trackable item in orbit around Earth with this visualization of all the stuff in space. [INTERACTIVE]
Keep on geeking!
@Summer_Ash, In-house Astrophysicist