![]() As temperatures rose and the metabolism of marine animals sped up, the warmer waters could not hold enough oxygen for them to survive. New research from the University of Washington and Stanford University combines models of ocean conditions and animal metabolism with published lab data and paleoceanographic records to show that the Permian mass extinction in the oceans was caused by global warming that left animals unable to breathe. What has been debated until now is exactly what made the oceans inhospitable to life – the high acidity of the water, metal and sulfide poisoning, a complete lack of oxygen, or simply higher temperatures. Some 96 percent of marine species were wiped out during the “Great Dying,” followed by millions of years when life had to multiply and diversify once more. Long before dinosaurs, our planet was populated with plants and animals that were mostly obliterated after a series of massive volcanic eruptions in Siberia.įossils in ancient seafloor rocks display a thriving and diverse marine ecosystem, then a swath of corpses. The largest extinction in Earth’s history marked the end of the Permian period, some 252 million years ago. Justin Penn and Curtis Deutsch/University of Washington The images below the line represent some of the 96 percent of marine species that died during the event. At the top is the supercontinent Pangaea, with massive volcanic eruptions emitting carbon dioxide. The color of the water shows the temperature change, with red being most severe warming and yellow less warming. A greater percentage of marine animals survived in the tropics than at the poles. They did find that the whale had consumed plants and invertebrates it might have "scooped up from the bottom of the Bay," where it was sighted in early May, which "supports the Center's ongoing field observations that gray whales are feeding while inside San Francisco Bay," according to the announcement.This illustration shows the percentage of marine animals that went extinct at the end of the Permian era by latitude, from the model (black line) and from the fossil record (blue dots). Scientists couldn't determine the cause of death for the second whale, which appeared to have died suddenly despite being "in excellent body condition," according to Marine Mammal Center officials. The body of that whale, a 37-foot adult male gray whale, was also found in the Point Reyes National Seashore on Saturday, but on the north end of Agate Beach. The second vessel strike resulted in damage akin to "severe whiplash" to a human involved in a car crash and was the likely cause of death, center officials said Thursday in a news release, which also details the results of a second whale necropsy performed at around the same time. RELATED: Whale spends record 10 weeks in SF Bay. It also shows that the animal was likely hit by two ships or large boats in separate collisions based on the presence of a large, slowly healing, older scar on its back, sea lice on the wound, multiple rib and spinal fractures under the scar, as well as more recent skull fractures, hemorrhaging and muscle damage to the area where the head connects to the body, according to Marine Mammal Center officials. The adult male whale was found dead a mile offshore last Saturday before washing up on North Beach in the Point Reyes National Seashore the next day.Ī necropsy performed by a team of 11 scientists from the Marine Mammal Center and the California Academy of Sciences shows the 39-foot whale was emaciated at the time of death. SAN FRANCISCO - A gray whale that died after spending at least 75 days in the San Francisco Bay was likely killed by a combination of malnutrition and trauma caused by a collision with a maritime vessel, according to officials from the Marine Mammal Center. ![]() A gray whale that died in the SF Bay was likely killed by a combination of malnutrition and trauma, says officials from the Marine Mammal Center. ![]()
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