MI weekly selection #469
Martian meteorite suggests no life on Red Planet
After examining the remnants of a meteorite knocked loose from Mars 1.3 billion years ago, scientists found the 725-gram rock had only trace amounts of exposure to hydrogen, almost certainly confirming there has not been life on the Red Planet.
It’s our own fault dogs can bend us to their will
The ratio of fast-twitch to slow-twitch facial muscles in dogs is closer to that of humans than wolves, and those muscles are behind the facial expressions dogs use to get people to do what they want. So-called puppy dog eyes are probably an evolutionary phenomenon caused by humans selectively breeding dogs that communicated using facial expressions.
Stonehenge surrounded by thousands of prehistoric pits
Researchers using electromagnetic detection devices surveyed 2.5 square kilometers around Stonehenge and found the ancient structure was once surrounded by thousands of pits. According to the study, a team of archeologists found that at least 415 large pits (2.4 meters in diameter) and 3,000 smaller pits may have been dug to trap wild game.
Seascapes contributed to ancient genomes across Europe
By examining the genomes of ancient Maltese remains, scientists have unlocked a possible answer to the mystery of genetic population variation across prehistoric Europe. The data suggests that sea travel played a large part, with Malta in particular being difficult to access and thus less exposed to the genetic variation that helped other European population adapt in prehistoric times.
Some parasites thrive by making hosts nice-looking
A new study suggests some sexually transmitted parasites, such as Toxoplasma gondii, may produce changes in the appearance and behavior of the human host. Date shows people with the parasite were seen as healthier and more attractive, either as a byproduct of the infection or as the result of the manipulation of the parasite to increase its spread to new hosts.