Discovered: Pigging out is a bigger health concern than starvation; Christmas trees haven't evolved much in 100 million years; Rhesus monkeys have no rhythm; say hi to this newly discovered primate.

Overeating outstrips undereating. You're unlikely to hear impassioned pleas from celebrities about the plight of the obese, but according to a large new study about the state of world health, overeating causes more health problems than hunger on average. The Global Burden of Disease was compiled by 500 scientists working from 50 countries. They found that between 1990 and 2010, it became more common to develop health problems from being underweight than from being undernourished. "A greater amount of disease burden has occurred because people are fat and have too much to eat, as opposed to having too little to eat," says the University of Queensland's Alan Lopez, one of the project's researchers.  [New Scientist]

Rhesus monkeys can't step to the beat. Because they can't hear it. University of Amsterdam and National Autonomous University of Mexico researchers have found that rhesus monkeys can't perceive beat induction, or the ability to notice regular patterns in rhythm. The scientists hooked up electrodes to the rhesus monkeys' brains, finding that they were unresponsive to stimuli that human babies perceived in terms of beat. They conclude that beat induction remains skill unique to humans. [Science Daily]

Speaking of primates... A team of researchers stalking Borneo have found a new one. And it's just so darn cute. That little wide-eyed guy to the right is a new species of slow loris, officially names Nycticebus kayan. A team of researchers from the U.K. and the U.S. were studying other species of slow loris in forested areas of Borneo and Philippines when they came across the nocturnal  deceptively dangerous creature. The Nycticebus kayan's bite is toxic. What's unfortunate about the finding is that the new species will go into textbooks already on the endangered list, according to Oxford Brookes University's Anna Nekaris: "In Borneo in particular, from where three of the new species hail, this will mean that three new lorises will be added as threatened to some degree on the IUCN Red List of threatened species. With more than 40% of the world's primates already threatened with extinction, this brings the toll even higher."

The more things change, the more Christmas trees stay the same. Christmas didn't exist 100 million years ago—Jesus's birth was still a long way off, historically. But if you had bought one of the conifers commonly propped up in living rooms during December back then, it would be almost genetically identical to one you'd buy today. Université Laval researchers in Canada compared the genomes of current spruce, pine, and fir trees with fossils dating back to dinosaur eras, finding remarkable similarity. Flowering plants have evolved a lot since then, but, "the macrostructure of the conifer genome has been remarkably stable over the ages," according to researcher Jean Bousquet. [Université Laval]