Search results
Results from the WOW.Com Content Network
"Typical sharks", such as requiem sharks, have tails with the upper lobe longer than the lower. The upper lobe is turned upwards at a moderate angle relative to the body, which balances cruising efficiency with turning ability. The thresher sharks have an extreme example of this tail in which the upper lobe has evolved into a weapon for ...
In elasmobranchs (sharks and rays) the spiracle bears a small pseudobranch that resembles a gill in structure, but only receives blood already oxygenated by the true gills. [7] The function of the pseudobranch is unknown, but it is believed that it supplies highly oxygenated blood to the optic choroid and retina and may have baroreceptor ...
Sharks are much more sensitive to electric fields than electroreceptive freshwater fish, and indeed than any other animal, with a threshold of sensitivity as low as 5 nV/cm. The collagen jelly, a hydrogel , that fills the ampullae canals has one of the highest proton conductivity capabilities of any biological material.
Roman emperor Domitian is believed to have put on a sea battle in the Colosseum in 85 AD, for instance. The “Gladiator II” naumachia raises the stakes by adding sharks, although that is ...
Many sharks can contract and dilate their pupils, like humans, something no teleost fish can do. Sharks have eyelids, but they do not blink because the surrounding water cleans their eyes. To protect their eyes some species have nictitating membranes. This membrane covers the eyes while hunting and when the shark is being attacked.
Locals have nicknamed the area Shark Park in part because many younger great white sharks congregate there for brief stints to enjoy the relatively warmer spring and summer water.
It typically reaches 2.5 m (8.2 ft) in length and a weight of 135 kg (298 lb); North Atlantic sharks grow larger than Southern Hemisphere sharks and differ in coloration and aspects of life history. Gray above and white below, the porbeagle has a very stout midsection that tapers towards the long, pointed snout and the narrow base of the tail.
Spoiler alert! We're discussing plot points of 'Gladiator II' (in theaters now), so if you haven't seen it yet, retreat. Pack up your dusty sandals and brutal weapons, folks.