injury is damage to the brain which is not hereditary, degenerative, or
congenital. It is often caused by a physical trauma, such as a car
crash, fall, or sports mishap. Other times the brain injury is acquired
through medical conditions such as stroke or lack of oxygen. Here are
ways brain injury can affect the body.
The car-tire-size opah is striking enough thanks to its rotund, silver
body. But now, researchers have discovered something surprising about
this deep-sea dweller: It’s got warm blood.
That makes the opah (Lampris guttatus) the first warm-blooded fish every discovered. Most fish are exotherms, meaning they require heat from the environment
to stay toasty. The opah, as an endotherm, keeps its own temperature
elevated even as it dives to chilly depths of 1,300 feet (396 meters) in
temperate and tropical oceans around the world.
“Increased temperature speeds up physiological processes within the
body,” study leader Nicholas Wegner, a biologist at the National Oceanic
and Atmospheric Administration (NOAA) Fisheries’ Southwest Fisheries
Science Center in La Jolla, California, told Live Science. “As a result,
the muscles can contract faster, the temporal resolution of the eye is
increased, and neurological transmissions are sped up. This results in
faster swimming speeds, better vision and faster response times.”…
Jellies are cnidarians—literally “stinging animals.” Using nematocysts (Nuh-mah-toe-SIS-tss) tucked into cnidocytes (nye-doe-SIGHTs) triggered by cnidocils (nye-doe-SILLs), they’re equipped with specialized stingers that make quick work of their prey.
Instead of blinking, guitarfish pull their eyeballs into their heads using specialized muscles.
And this is very helpful when you live in sandy environments. Eye retraction behavior has evolved independently in some vertebrate linages such as mudskippers (fish), frogs and salamanders (amphibians), and cetaceans (mammals). And like sharks, the giant guitarfish (Rhynchobatus djiddensis) doesn’t have eyelids that close all the way, so it can’t blink.
When the guitarfish hunts, it protects itself with an eye-catching method: retracting its eyes almost completely into its head, leaving a craterlike depression. Using high-speed video, researchers found a guitarfish could sink its eye nearly 40 mm.
The eye retraction distance is nearly the same as the diameter of the eyeball itself, indicating that eye retraction in the giant guitarfish is probably one of the largest among vertebrates and likely represents a novel eye protection behavior of elasmobranch fishes.
Some rays and skates, however, have the same muscle arrangement as guitarfish, so researchers are eyeing them for future studies.