So I asked leading shark ethologist and behaviourist, Professor Samuel 'doc' Gruber to elaborate. After pointing out how much pain women feel when they give birth, making the point that suffering has no effect on reproduction, he reminded me that sharks evolved their mating behaviours and the physical structures involved, separately from other animals.
Researchers in Australia have discovered a secret weakness of one of the ocean's most impressive predators.
The scientists, who examined the retinas of 17 different species of shark, discovered that the creatures had only one type of colour-sensitive cell, known as a cone cell, in their eyes.
A study by Simon Oliver at the School of Ocean Sciences, Bangor University describes the first observations of thresher sharks venturing into shallow coastal waters to interact with cleaner wrasse, a type of small fish that groom other fish species.
Thresher sharks live in the open oceans and much of the knowledge of them to date is based on fisheries bycatch. This study just published in published in PLoS ONE, (14 March 2011) examined the behaviour of these elusive sharks as they invite cleaners to remove parasites and dead tissue.
House Bill (HB) 2838 was introduced to the Oregon State Legislature on 11 January 2011 by Representative Brad Witt (D-Clatskanie) to prohibit the possession, sale, trade, and distribution of shark fins in Oregon. Western ports such as those in Oregon and California are major entry points for shark fin distribution in the United States.
It has been widely known that sharks have a special sensory organ on their heads, called the ampullae of Lorenzini, which enable them to detect the very weak electrical fields that prey emit when they swim or bleed.
But now scientists have found that a gel-like substance plays a big role in this process known as electroreception, explaining why sharks pursue bloody victims, even when other easy target´s prey is around, and the gushing blood obscures the shark´s vision and smell.
As many as 400 megalodon teeth were found at the sites, giving rise to this theory. The size of most of the teeth, about 0.6 to 2.8 inches, suggests that the majority had come from juveniles and embryonic sharks.
Juvenile teeth are different from the small teeth from adults or the dwarf species of the megalodon. In all, it is estimated that the teeth came from 21 juvenile megalodons and seven adults, possibly the mother sharks.
AB 376 was authored by Assemblymembers Paul Fong (D-Cupertino) and Jared Huffman (D-San Rafael). AB 376 passed the Assembly by a vote of 65 to 8 on May 23rd and the Senate on September 6th with a vote of 25 to 9. Both of the votes were bipartisan. We thank Assemblymen Fong and Huffman for fighting so long and hard for this bill.
Sharks are known to "dive" frequently through the water column and many functions have been attributed to the behaviour, such as thermoregulation, search and reduction of the COT. Few studies, however, have been able to frame these in conjunction with theoretical optima and test predictions for differing movement structures.
Dr Jonathan Cox from the University’s Department of Chemistry has been working with researchers from the University of Cambridge and the Natural History Museum in London, testing a scale model of a hammerhead shark in a flow tank to see how the water flows around the nasal cavity of its strange flattened head.
Weighing in at up to 3,000 pounds and attaining lengths of 18 feet, Great White sharks are among the ocean’s most feared yet revered inhabitants. Having a face-to-face encounter with the ocean’s apex predator is a bona-fide adrenaline rush, with divers worldwide shelling out mega bucks and travelling great distances for the privilege.
Boasting pristine blue water with 100-foot visibility, Guadalupe Island situated west of Baja California, Mexico, is one of the world’s premier Great White destinations.
A new 4-million-year-old fossil from Peru described in this month’s issue of the Journal of Vertebrate Paleontology provides important evidence suggesting the shark’s origins may be more humble than previously believed.
Dana Ehret, Gordon Hubbell and Bruce MacFadden studied an exceptionally well-preserved fossil of a species of white shark (Carcharodon sp.) from Peru (estimated to be about 5 m long by the authors), consisting of a complete jaw with 222 teeth, and 45 vertebrae, in their paper.
