Science News Roundup: U.S. builds alliances in 'wild, wild west' of space: general; Bird numbers plunge in U.S. and Canada with people to blame

Following is a summary of current science news briefs.

Alien enthusiasts gather in Nevada desert near secretive Area 51

UFO enthusiasts began descending on rural Nevada on Thursday near the secret U.S. military installation known as Area 51, long rumored to house government secrets about alien life, with local authorities hoping the visitors were coming in peace. Residents of Rachel, Nevada, a remote desert town of 50 people about 12 miles outside the base, worried their community might be overwhelmed by unruly crowds turning out in response to a recent viral social-media invitation to "storm" Area 51.

Bird numbers plunge in U.S. and Canada with people to blame

From grasslands to seashores to forests and backyards, birds are disappearing at an alarming rate in the United States and Canada, with a 29% population drop since 1970 and a net loss of about 2.9 billion birds, scientists said on Thursday. People are to blame, the researchers said, citing factors including widespread habitat loss and degradation, broad use of agricultural chemicals that eradicate insects vital to the diet of many birds, and even outdoor hunting by pet cats.

Distant asteroid calamity shaped life on Earth 466 million years ago

The cataclysmic asteroid impact off Mexico's coast that doomed the dinosaurs 66 million years ago was not the only time an astronomical event shaped the history of life on Earth. Scientists on Wednesday said dust spawned by a gigantic collision in the asteroid belt between Mars and Jupiter 400 million years earlier triggered an ice age on Earth that ushered in a significant increase in marine biodiversity.

Scientists reconstruct skeleton of elusive, pre-historic human

Researchers in Israel say they have reconstructed the skeleton of a pre-historic human from a long-extinct and elusive species using DNA found in the pinky bone of a 13-year-old girl who died 70,000 years ago. Little is known about the Denisovans, who were ancient relatives of the more familiar Neanderthals and our own species. Their existence was only recently discovered and has fascinated scientists worldwide.

U.S. builds alliances in 'wild, wild west' of space: general

The new U.S. Space Command is working with allies in the "wild, wild west" of space and will harden future satellite networks against attacks, the unit's top general said, as the Trump administration reorganizes its military space bureaucracy. General John Raymond, head of the Space Force created in August, said Washington would work with the Five Eyes intelligence alliance, composed of Australia, Canada, New Zealand, the United Kingdom and the United States.

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