Why ancient Nutcracker Man ate tiger nuts
An Oxford University study has concluded that our ancient ancestors who lived in East Africa between 2.4 million and 1.4 million years ago survived mainly on a diet of tiger nuts.
Tiger nuts are edible grass bulbs still eaten in parts of the world today. The results were published in the journal PLOS ONE. They also suggests that these early hominins may have sought additional nourishment from fruits and invertebrates, like worms and grasshoppers.
Study author Gabriele Macho examined the diet of Paranthropus boisei nicknamed Nutcracker Man because of his big flat molar teeth and powerful jaws through studying modern-day baboons in Kenya.
Scholars have debated why this early human relative had such strong jaws, indicating a diet of hard foods like nuts, yet their teeth seemed to be made for consuming soft foods.
Tiger nuts, which are rich in starches, are highly abrasive in an unheated state. Macho suggests that these hominins teeth suffered abrasion and wear and tear due to the starches. Modern baboons eat tiger nuts, and the study finds that baboons teeth have similar marks, giving clues about their pattern of consumption. This food would have contained sufficiently high amounts of minerals, vitamins and the fatty acids that would have been particularly important for the ancient Nutcracker Man brain.
In order to digest the tiger nuts and allow the enzymes in the saliva to break down the starches, the hominins would need to chew the tiger nuts for a long time. ox.ac.uk
Genome test authenticates quality of great chocolate
Until now, other than depending on their taste buds, chocolate connoisseurs had no way to know whether they were getting what they paid for. In the Journal of Agricultural and Food Chemistry, scientists report developing a method to authenticate the varietal purity and origin of cacao beans, the source of chocolates main ingredient, cocoa.
Researchers had found ways to verify through genetic testing the authenticity of many other crops, including cereals, fruits, olives, tea and coffee, but those methods arent suitable for cacao beans.
Applying the most recent developments in cacao genomics, a team led by Dapeng Zhang of the USDA/Agricultural Research Service was able to identify a small set of DNA markers called SNPs (snips) that make up unique fingerprints of different cacao species. The technique works on single cacao beans and can be scaled up to handle large samples quickly. American Chemical Society
Older trees, not saplings, put on the pounds
Trees put on weight faster and faster as they grow older, according to a new study in the journal Nature. The finding that most trees growth accelerates as they age suggests that large, old trees may play an unexpectedly dynamic role in removing carbon from the atmosphere.
Richard Condit, staff scientist at the Smithsonian Tropical Research Institute in Panama, devised the analysis to interpret measurements from more than 600,000 trees belonging to 403 species.
Rather than slowing down or ceasing growth and carbon uptake, as we previously assumed, most of the oldest trees in forests around the world actually grow faster, taking up more carbon, Condit said.
If human growth would accelerate at the same rate, we would weigh half a ton by middle age and well over a ton at retirement, said Nate Stephenson, lead author and forest ecologist with the U.S. Geological Survey. stri.si.edu