October 18, 2013

Sensitive DNA tests on samples of hair recovered from the Himalaya indicate that the Yeti may actually exist, reported Bryan Sykes, a professor of genetics at the University of Oxford in the United Kingdom. Although this unexpected finding could potentially rank as one of the greatest zoological discoveries in history, fans of the legendary Yeti may be somewhat disappointed. The tests also show that the Yeti is not what people think it is.

The Yeti, which has also been called the Abominable Snowman, is said to be a creature with a human-like face and ape-like body that lives on Mount Everest and other mountains of the Himalaya range. According to local legend, the Yeti sometimes comes down from the mountains to attack villagers.

The legendary Yeti is a ape-like creature with a human-like face who lives in remote areas of the Himalaya. The real Yeti is probably something entirely different. (World Book illustration by Ted Lewis)

Many people are fascinated by the idea that a large primate like the Yeti–or its American cousin, Bigfoot–could survive in remote wilderness unexplored by modern science. Cryptozoologists, people who study and search for legendary creatures, have investigated the Yeti for decades. Sensational reports of Yeti sightings have been exposed as hoaxes and fakes in the past, and this has led many skeptics to dismiss the creature as pure fantasy.

However, reports of Yeti sightings continue to this day, and cryptozoology enthusiasts argue they demand explanation. Sykes made news in 2012 when he publicly asked wildlife scientists, museums, and Yeti believers to send him written descriptions and photos of any evidence they might have of the creature. If the descriptions looked promising, the researchers requested the physical samples and then tested the samples’ DNA to determine which species they came from.

Sykes and his team conducted sophisticated genetic tests on two samples of supposed Yeti hair discovered in the Himalaya: one found in Ladakh–a region in Jammu and Kashmir, the northernmost state in India; and another from Bhutan to the east. They compared the samples to the genetic codes of other animals from collections gathered over many years from all over the world. The tests revealed that the hair was from a mammal, but it did not match samples from known primates. Surprisingly, the DNA from the two samples matched up almost exactly with DNA from the 40,000-year-old jawbone of a Norwegian polar bear.

The researchers do not believe that the Himalayan Yeti actually represents an isolated population of polar bears. Instead, they theorize that the region is home to an unknown hybrid bear species that developed from matings between polar bears and brown bears somewhere in northern Asia during the last Ice Age, when the ranges of those bears overlapped. They point to antique Tibetan texts that describe the Yeti as a shy bear-like creature that is sometimes aggressive towards humans when encountered in its remote mountain domain. The scientists also point out that the animal may still survive in remote areas of the Himalaya, giving Yeti enthusiasts hope that the legendary creature may one day be found.

Additional World Book articles:

• Folklore
• Hillary, Sir Edmund Percival
• Journey to the Top of the World by Sir Edmund P. Hillary (a special report)

Polar bears are more distantly related to other bears than previously thought, according to new research. Scientists have long known that polar bears share a common ancestor with brown bears. Previous research had shown that the split between the two groups occurred relatively recently, about 150,000 years ago. But in new research, scientists found that the split took place much earlier, about 600,000 years ago. Thus, polar bears are more distinct from other bears than scientists thought.

The research helps scientists to understand the history of how polar bears have evolved (developed over many generations). Polar bears have many adaptations (features) that help them to survive on Arctic sea ice. These adaptations help to make them different from brown bears. Polar bears would have had to evolve these adaptations in relatively little time if they had split from the same ancestor as brown bears only 150,000 years ago.

The new research involved studying bear DNA, which carries hereditary information. Scientists compared the DNA of black bears, brown bears, and polar bears. Comparing the DNA enabled scientists to estimate the date at which polar bears and brown bears shared a common ancestor. Earlier research into polar bear origins used DNA from a different part of the cell. Most DNA is housed in the cell’s nucleus (a body at the center of the cell). However, a small amount of DNA is housed in mitochondria (tiny bodies in the cell that burn chemical energy). The earlier research used DNA from the mitochondria to estimate the first appearance of polar bears. The new research used DNA from the nucleus. This information provided more data about polar bear origins.

The hardy polar bear lives along the frozen shores and in the icy waters of the Arctic Ocean. Polar bears have a thick, white coat that blends in with the ice and snow. They swim strongly by paddling with their front legs and stretching their head forward. (Marvin E. Newman, DPI)

Scientists suggest the different estimates for the first appearance of polar bears may have been caused by later matings between polar bears and brown bears. Such mating is known to occur, especially when polar bear populations are under stress. Thus, the mitochondria results may record breeding between polar bears and brown bears about 150,000 years ago. In fact, the research suggested that polar bears have gone through several so-called bottlenecks, periods during which relatively few polar bears survived. These bottlenecks may have corresponded to reduced sea ice or other climate changes that made it more difficult for polar bears to survive. Polar bears are currently considered vulnerable to extinction because of a loss of sea ice caused by climate change, and scientists have shown that some polar bears and brown bears have breed in recent years. The research was published online in the journal Science.

Additional World Book articles:

The Great Meltdown (a special report)