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The upper left jaw of an ancient human fossil found in Israel. Photo: Israel Hershkovitz / Tel Aviv University
Axios' Erin Ross writes: A ridge of teeth discovered in a cave in Israel are between 177,000-194,000 years old, according to a paper published today in Science.
The teeth appear to be human, and if they are, would be the oldest anatomically modern human fossil found outside of Africa and the oldest fossil with modern human traits found to date.
What it means: Fossils like these, and new gene sequencing tools, are starting to answer questions about when modern humans left Africa, and when, exactly, they became human. The find in Israel suggests modern humans may have left Africa earlier than previously thought.
What they found: Debbie Guatelli-Steinberg, a paleoanthropologist at Ohio State University who was not involved in the study, tells Axios that the specimen's teeth and jaw structure are most like humans, and don't have Neanderthal features.
And, they didn’t just find a jaw — they unearthed sophisticated stone tools, too.
Dig deeper: Read Erin's full story here.
Plastic pollution, such as this Nike logo, helps foster certain diseases like white syndrome coral disease seen here. Photo: Joleah Lamb / Cornell University
The billions of pieces of plastic waste hovering in the oceans of the Asia-Pacific region are causing a 20-fold increased risk of diseases deadly to coral reefs, according to a new study published in Science Thursday, Axios' Eileen Drage O'Reilly reports.
Why it matters: The estimated 11.1 billion plastic items lodged around the Asia-Pacific coral reefs boost the risk of coral contracting skeletal eroding band disease, white syndromes, and black band disease, they found. About 275 million people in the region rely on the reefs for food, tourism, marine biodiversity, and coastal protection.
"Plastic is a triple whammy for coral infections — it abrades and cuts open the skin of the coral, and then can convey pathogenic microorganisms. [It] shades and cuts off water flow," study author C. Drew Harvell tells Axios.
Dive deeper: Read the rest of Eileen's story here.
The Mexican axolotl Ambystoma mexicanum is a model organism for regeneration research. Photo: IMP Vienna
The critically endangered Mexican axolotl can regenerate body parts better than practically any other vertebrate on the planet. If a limb is lost, a limb can be regrown.
"We need to figure out why and hopefully mimic that in humans," says Northeastern University's James Monaghan, who studies the biology of regeneration in the salamander species. The programs of development that give us our forms in the womb shut down in humans as we grow — but axolotls and some other animals keep that ability forever.
For a long time, researchers have tried to sequence the animal's genome in order to better understand how cells can know what was lost and what to regenerate. But the tiny salamander has a big genome — at 32 billion base pairs, it's ten times the size of the human genome — filled with lots of repetitive sequences that make it hard to sequence. It is like putting together a puzzle that has a lot of the same pieces, says Monaghan.
What's new: Scientists figured out a way to piece together the axolotl genome and this week reported a nearly complete sequence.
One more thing: The researchers found the axolotl's developmentally important genes aren't as big as their other genes. "There has been selection to keep them small," says Monaghan. It is speculation at this point but it could be so they can be transcribed quickly when needed — say, during regeneration.
Thanks for reading. Don't forget to check the science stream throughout the week.