The first insects had way more than six legs - Science | AAAS

Sled dogs pull sleds for recreation and work. They’re some of Earth’s most powerful athletes, traversing thousands of miles of rough terrain in sub-zero temperatures, through blinding snow, and biting winds. Sled dogs have been helping humans travel across the planet’s coldest regions for centuries, hauling supplies, people, and equipment across the snow and ice. In the process, this important role that goes above and beyond simply being “man’s best friend” could have a visible impact on their evolution.

The spacecraft delivered materials and equipment for new research studies to the station.

ORCID: orcid.org/0000-0001-8061-88361, Yaser Mehri2, Ali Abdolrazaq Sabbar3, Mohammad Javad Nahvinia3 & … Mohammad Hosein Omid2 We’re sharing this article early to provide faster access to peer-reviewed, accepted research. It is citable and carries a permanent DOI. This version is subject to further edits and will be replaced automatically by the final Version of Record. All legal disclaimers apply.

The history of life on Earth doesn’t start with the Cambrian Explosion. However, this was the point in time that nearly all major animal groups appeared, proliferated, and diversified. It wiped out 90% of life on Earth, turned the oceans into graveyards – and it very nearly ended life on our planet entirely