They found that often, the number of species in a lineage expanded after that branch of the fish family tree evolved bioluminescence. The researchers argue that bioluminescence is key to much of the ocean's species diversity. "So you have to ask how reproductive isolation comes about." "In the ocean, there are no physical barriers to keep different groups from reproducing with one another," said John Sparks, study co-author and curator-in-charge of the American Museum of Natural History's Department of Ichthyology, in an interview with The Washington Post. That helped them map out a startling discovery: Fish evolved luminescent capacities at least 27 different times. Some of these fish developed bioluminescence on their own, through cellular chemical reactions, while other species developed specialized organs to hold glowing bacteria.ĭavis and his colleagues developed a family tree of ray-finned fish, which includes almost 99 percent of fish species. Today, nearly 1,500 different species of fish produce light from their heads, glowing stripes on their bodies, bright dangling parts under their mouths or eyes, or even from their stomachs. Scientists have found evidence of glowing fish as far back as the Jurassic era, when dinosaurs roamed the earth. "They're among the most abundant vertebrates on the planet in terms of mass, but the average person doesn't know anything about them," Professor Davis told National Geographic.īioluminescence is hardly a new phenomenon. Cloud State University, lead author on the new study. The 250 species of lanternfish make up two-thirds of all deep sea fish by weight, according to Matthew Davis from St. The sheer volume of these glowing fish boggles the mind. The dark, cold depths of the ocean sparkle with trillions of glowing fish, report scientists in the current issue of PLOS ONE.Ĭreatures with names like lanternfish and dragonfish and ponyfish shine like fireflies, filling the ocean with countless sources of light. 6 to realize we are in a perilous state.” “We don’t have to go much farther than Jan. Libraries from the Obama Foundation back through the Roosevelt Institute signed, with the exception of the Eisenhower Foundation.“I think there’s a great concern about the state of our democracy at this time,” Mark Updegrove, head of the LBJ Foundation, told The Associated Press. Trump excoriates the country’s legal system as he faces multiple criminal indictments.The statement does not name any particular person or party. Polls show many Republicans back former President Donald Trump’s unsubstantiated claims that the 2020 election was stolen, while Mr.
Most living presidents have generally avoided commenting directly about the polarized state of U.S. security and prosperity, said signers.“But that interest is undermined when others see our own house in disarray,” the statement concluded.The idea for the library alliance originated at the George W.
#Deep sea glowing fish free
On Thursday, 13 presidential libraries and associated foundations dating back to Herbert Hoover issued a joint call for Americans to recommit to founding democratic values, including the rule of law, tolerance for other views, and commitment to peaceful transfers of power.“As a diverse nation of people with different backgrounds and beliefs, democracy holds us together,” said the statement.Americans have a strong interest in supporting democratic values around the world because free societies everywhere contribute to U.S.
They look backward and forward, telling the story of an administration’s course while trying to teach its lessons to future generations.That’s why their message to the United States this week is important. They are part museum, part memorial, part repository.
Presidential libraries play a unique role in U.S.
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