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A study involving Simon Fraser University researchers and published today in the journal Science has found evidence for the genomic basis of how new species evolve, in adapting to different environments.

HOUSTON -- (May 15, 2014) -- A first-of-its-kind study this week suggests that the genomes of new species may evolve in a similar, repeatable fashion -- even in cases where populations are evolving in parallel at separate locations. The research is featured on the cover of the May 16 issue of Science.

The body's innate immune system is a first line of defense, intent on sensing invading pathogens and wiping them out before they can cause harm. It should not be surprising then that bacteria have evolved many ways to specifically evade and overcome this sentry system in order to spread infection.

The immune system's B cells protect us from disease by producing antibodies, or "smart bullets," that specifically target invaders such as pathogens and viruses while leaving harmless molecules alone. But how do B cells determine whether a threat is real and whether to start producing these weapons?

An international team of life scientists shows in the May 16 issue of the journal Science how and why these cells respond only to true threats.

PITTSBURGH—Clouds play a critical role in Earth's climate. Clouds also are the largest source of uncertainty in present climate models, according to the latest report of the Intergovernmental Panel on Climate Change. Much of the uncertainty surrounding clouds' effect on climate stems from the complexity of cloud formation.

This news release is available in Spanish and Arabic.

The discovery of a near-complete human skeleton in a watery cave in Mexico is helping scientists answer the question, "Who were the first Americans?" The finding, reported in the 16 May issue of the journal Science, sheds new light on a decades-long debate among archaeologists and anthropologists.

Deciphering the ancestry of the first people to populate the Americas has been a challenge.

WASHINGTON (May 15, 2014)—The skeletal remains of a teenage female from the late Pleistocene or last ice age found in an underwater cave in Mexico have major implications for our understanding of the origins of the Western Hemisphere's first people and their relationship to contemporary Native Americans.

PULLMAN, Wash.—For more than a decade, Washington State University molecular anthropologist Brian Kemp has teased out the ancient DNA of goose and salmon bones from Alaska, human remains from North and South America, and human coprolites—ancient poop—from Oregon and the American Southwest.

His aim: use genetics as yet another archaeological record offering clues to the identities of ancient people and how they lived and moved across the landscape.

CHAMPAIGN, Ill. — A new study could help resolve a longstanding debate about the origins of the first people to inhabit the Americas, researchers report in the journal Science. The study relies on genetic information extracted from the tooth of an adolescent girl who fell into a sinkhole in the Yucatan 12,000 to 13,000 years ago.

Eastern Asia, Western Asia, Japan, Beringia and even Europe have all been suggested origination points for the earliest humans to enter the Americas because of apparent differences in cranial form between today's Native Americans and the earliest known Paleoamerican skeletons. Now an international team of researchers has identified a nearly complete Paleoamerican skeleton with Native American DNA that dates close to the time that people first entered the New World.

AUSTIN, Texas — The ancient remains of a teenage girl found in an underwater Mexican cave establish a definitive link between the earliest Americans and modern Native Americans, according to a new study released today in the journal Science.

Scientists have created a 'heavy' mouse, the world's first animal enriched with heavy but non-radioactive isotopes - enabling them to capture in unprecedented detail the molecular structure of natural tissue by reading the magnetism inherent in the isotopes.

Cave-diving scientist Patricia A. Beddows of Northwestern University is a member of an international team of researchers and cave divers this week announcing the discovery in an underwater Yucatán Peninsula cave of one of the oldest human skeletons found in North America.

Details of "Naia," a teenage girl who went underground to seek water and fell to her death in a large pit named Hoyo Negro ("black hole" in Spanish), will be published May 16 in the journal Science.

Stanford, CA—All living cells are held together by membranes, which provide a barrier to the transport of nutrients. They are also the communication platform connecting the outside world to the cell’s interior control centers. Thousands of proteins reside in these cell membranes and control the flow of select chemicals, which move across the barrier and mediate the flux of nutrients and information.

Her name is Naia, and for thousands and thousands of years, the skeleton of this young woman was buried underwater in an elaborate cave system in the Yucatan Peninsula after she had apparently fallen into what was then a dry deep pit.