Apes Have Mid-Life Crises Too.
Behaviorists believe that human life can be measured by a “happiness curve.” The general happiness of youth gives way in midlife to a dip, followed by increased happiness in later years. Surprisingly, that same pattern is seen in apes. Alexander Weiss, a primate psychologist at the University of Edinburgh in Scotland, has accumulated data from about over 500 chimpanzees and orangutans in zoos around the world. The measurement of their happiness, as reported by their human caretakers, follows essentially the same happiness curve as the one experienced by humans.
More at National Geographic.
Mammal That Survived While Dinosaurs Perished.
We know that mammals survived the mass extinction event that wiped out the dinosaurs. New research on a little known family of mammals has shed light on at least one survival strategy. Fossils of Necrolestes patagonensis, which translates into “grave robber,” literally took to ground. It appears to have spent most of its time deep underground where it lived in mole-like conditions. This, perhaps, proved to be a winning strategy. Although the family of mammals to which it belongs was thought to have become long extinct, the new fossil evidence suggests that the “grave robber” made it through this extinction event and outlived the dinosaurs by many millions of years before it, too, passed the torch.
Life on Mars??
NPR reports that scientists at NASA are on the verge of confirming a momentous martian soil discovery. The mars rover Curiosity has apparently tested some samples of martian soil and discovered methane, which can be a signature of life. But as Joe Palca reports for NPR, the scientists need more time to verify the discovery. John Grotzinger, NASA’s principal researcher, is quoted as telling NPR, “This data is gonna be one for the history books. It’s looking really good.” If, and it’s a big if, Curiosity has detected life on mars, it will be the first time it has ever been found outside of earth.
Naples Zoo Acquires New Old Species.
Florida’s Naples Zoo in Caribbean Gardens is getting a new species. For the first time, the zoo will exhibit a pair of male and female miniature zebus. Zebus are a kind of cattle — an ancient breed that was first domesticated some 6,000 years ago. Their domestication and use in agriculture in the Indian sub-continent is credited with jump-starting Eurasian peoples on the road to farms, towns, cities and modernity.
A Case of Mis-snaken Identity?
The beaked sea snake is among the deadliest of snakes. It was believed that the same species of beaked sea snake inhabited shallow waters in both Australia and Asia. A new DNA analysis has revealed that the Asian and Australian snakes are actually completely separate species that co-evolved. The phenomenon is known as convergent phenotypic evolution and it occurs when two distant species happen upon the same evolutionary pathways to success, leaving them physically very similar in appearance. In this case, both snakes live in very similar and specific habitat niches. Nevertheless, while they are useful for antivenom production, they are a major cause of death to fisherman in the shallow waters where they live.
How Dogs Decide What to Fetch.
Border collies are regarded as an extremely intelligent breed of dog. In one celebrated case, a border collie named “rico” had mastered a vocabulary of some 200 individual objects. In humans, behaviorists have found that the shape of an object is what toddlers use to categorize that and similar objects. For example, toddlers recognize a round toy such as a tennis ball and generalize it into a generic category for all ball-like objects. But how do dogs distinguish different named objects? University of Lincoln researchers conducted experiments with dogs and found that rather than shape, dogs distinguished objects based upon size and texture. So while dogs can learn to associate words with objects and to also generalize about those objects, they do so in a manner different from people.
Male Monkeys’ Diet Affects Behavior.
We are what we eat and so, too, are monkeys. A study of plant consumption by the red colobus monkey in Uganda’s Kibale National Park has demonstrated that the more estrogenic plants that these male monkeys ate, the more their behavior was affected. Estrogenic plants contain relatively high levels of hormones related to estrogen. Specifically, eating more estrogenic plants increased the hormone levels of estradiol and cortisol. These hormones affect sexual and physical aggressiveness in the monkeys. The study will soon focus on chimpanzees, which are our closest relatives. If the relationships between particular estrogenic plants and behavior holds up, it might someday inform scientists about the evolutionary changes that early human plant eaters underwent.
Hominids Already Used Stone-tipped Spears Half-a-Million Years Ago.
Before modern humans and before Neanderthals, a hominid ancestor known as Homo heidelbergensis had already perfected a technique for hand-crafting stone spear points and attaching them to wooden spears for hunting. New analysis of these spear tips and experiments to determine how they break upon impact have revealed that they were being produced far earlier than once thought — in fact some 500,000 years ago. Modern humans as well as their Neanderthal cousins adopted and used these ancient techniques in their own hunting. The complexity of the multi-step process involved in making the spears speaks to the behavioral complexity of these early human ancestors.
For Better Stealth Aircraft, Engineers Turns to Owls.
Owls can glide almost noiselessly when they are on the hunt. Military engineers recognize that whatever owls are doing right might be applicable to fighter aircraft design. So far, a systematic study of the owls’ wing structure reveals three distinct possible advantages: a stiff feathered leading tip where the air first makes contact with the wing, a soft downy coating along the width of the wing, and a flexible fringe of feathers at the trailing edge of the wing, where the air current ends. Scientists are not sure if just one or all of these features in combination are responsible for the owls’ stealthy maneuvers, but they intend to co-opt nature’s design.
For Chimps Every Season Is A Giving Season
Like humans, chimps bestow gifts on individuals they care about. In a study to determine whether gifting amongst chimp friends was a question of immediate quid pro quo or if it was based on a more enduring relationship, scientists from the University of California, Santa Barbara, studied gift-giving among a tribe of chimps. What they found was that, like humans, chimps were more randomly generous and less likely to keep score of what gifts they gave and received when the relationship was particularly strong. In weaker or more tenuous relationships, gift giving took on more of a scorecard or quid pro quo aspect.
“The Dirt: This Week in Nature” curated and written by Robert Raciti.