Search results
Results from the WOW.Com Content Network
The spiracle is often located towards the top of the animal allowing breathing even while the animal is mostly buried under sediments. [5] As sharks adapted a faster moving lifestyle some became obligate ram ventilators , breathing exclusively by forcing water through their gills by swimming; among these are requiem sharks and hammerhead sharks ...
Ampullae of Lorenzini are physically associated with and evolved from the mechanosensory lateral line organs of early vertebrates.Passive electroreception using ampullae is an ancestral trait in the vertebrates, meaning that it was present in their last common ancestor. [7]
The shark kidney excretes urea that is needed for the shark to have in its system so the shark does not become dehydrated from living in seawater. [14] Sharks hearts have two chambers. The shark heart's main importance is providing oxygenated blood to the entire body while filtering out the deoxygenated blood. [15]
The dusky smooth-hound (Mustelus canis), also called the smooth dogfish or the dog shark, is a species of houndshark in the family Triakidae. [1] This shark is an olive grey or brown in color, and may have shades of yellow or grayish white. Females live to 16 years and males have a lifespan of 10 years.
The intestines of a shark are much shorter than those of mammals. Sharks have compensated for this problem by having a spiral valve, or a scroll valve, inside the intestine to increase the absorbent surface of the intestine. By keeping digestible material in the ileum for an extended period maximum nutrient absorption is ensured.
Discover the latest breaking news in the U.S. and around the world — politics, weather, entertainment, lifestyle, finance, sports and much more.
Squalidae, more commonly known as dogfish, dog sharks, or spiny dogfish, [3] are one of several families of sharks categorized under Squaliformes, making it the second largest order of sharks, numbering 119 species across 7 families. [4]
Gaping is part of the shark agonistic display, and is also found in snakes such as the cottonmouth, and in birds ranging from seagulls to puffins to roosters. A number of species of bird use a gaping, open beak in their fear and threat displays. Some augment the display by hissing or breathing heavily, while others clap their beaks. [2]