Sea otter teeth more than twice as tough as ours

first_imgSea otters, which often dine on clams, crabs, and other shelled creatures, have unusually chip-resistant teeth, a new study suggests. Lab tests show that the enamel coating the teeth of sea otters (Enhydra lutris, shown) is up to two-and-a-half times tougher than human tooth enamel, thanks largely to the enamel’s microstructure. In all mammal enamel, the tiny crystals of calcium phosphate that give the tooth’s surface its hardness are separated by thin layers of protein-rich gel that help prevent cracks from propagating. In human enamel, there are about 14 of these crack-arresting layers per millimeter of tissue, but sea otter enamel has about 19 such layers per millimeter—an increase that substantially boosts the surface toughness of the teeth. Interestingly, the researchers report online today in Biology Letters, previous studies have found that the early hominin, or member of the human family, Paranthropus boisei—which lived in Africa between 1.2 million and 2.3 million years ago and has been nicknamed “Nutcracker Man” due to its large, thick-enameled molars—also had about 19 of these crack-arresting layers of protein gel per millimeter of enamel. That spacing suggests that P. boisei’s teeth may have been more chip-resistant than scientists have previously recognized, which may in turn revamp notions about the diet of these early humans.last_img read more

Read More

Farright MP in hot water over threats

first_imgThe neofascist Golden Dawn faced fresh scrutiny on Monday after the party’s spokesman allegedly threatened the lives of anti-fascist protesters at a party gathering on the island of Crete on Sunday while another MP unfurled the flag used by the 1967-74 junta. Police on Monday submitted to the prosecutor’s office in the port of Iraklio video footage of Golden Dawn MP Ilias Kasidiaris threatening officers. Kasidiaris swore at the officer in charge for not keeping anti-fascist protesters away from the venue of the gathering and told him that there would be victims unless the protesters were moved away. “Believe me, you will have dead people by tonight,” he can be heard telling the police in video footage uploaded onto the Internet. Later in the day, Kasidiaris claimed that he meant there would be victims if police did not take the necessary security measures. The incident was condemned by political parties, with socialist PASOK referring to “unacceptable threats and verbal abuse” and leftist SYRIZA accusing the party of trying to create “a bloodbath.” In a separate event, Kasidiaris was filmed explaining how the party’s 18 lawmakers aim to take advantage of their parliamentary immunity and other privileges. “We can now carry guns legally and will not be arrested on the spot if there is an incident,” he said. “This makes us a bit more relaxed about our movements.” Another neofascist MP, Christos Pappas, unfurled the flag used by the 1967-74 junta at the event on Crete, to applause from party supporters. The coast guard on Crete is launching its own internal investigation after one of its officers was found to have used one of the service’s official cars to attend the Golden Dawn event. Source: Kathimerini Facebook Twitter: @NeosKosmos Instagramlast_img read more

Read More