Posts Tagged ‘Elephants’

Why Elephants Have Trunks

Posted by admin on June 1, 2012  |   No Comments »
Packy’s huge trunk. Credit: Oregon Zoo

Packy’s huge trunk. Credit: Oregon Zoo

Evolving larger takes ten times more generations than becoming smaller, according to research published this week in Proceedings of the National Academy of Sciences. Biologists estimate elephant-sized mammal requires 10 million generations to evolve from rabbit-sized one.

This new research adds to our knowledge about why elephants have trunks. While children’s stories offer different explanations, scientists remain firm in their conviction that elephants evolved from much smaller animals possibly with smaller trunks—similar to a tapir.

Trunks evolved to stay in contact with ground

As the elephant ancestors’ size increased, their trunks evolved to stay in contact with the ground. In a 10-13 foot tall animal, either the neck has to be long enough to, or there needs to be another approach. Because elephants’ teeth and jaws became massive to be equal to the task of grinding the branches and thorns of acacia trees, their heads were too heavy to be supported by anything but a short, thick neck.

Snorkel?

An alternative theory, still under consideration and awaiting more study of fossil evidence, is that elephants may be related to manatees and dugongs. In other words, a common ancestor of manatees and elephants could have used a trunk as a snorkel.

From 55 million years of evolutionary data, we know that two or three species remain of the 164 elephant relations that lived in the past. The extinct forms ranged from deserts to mountaintops, on every continent except Australia and Antarctica. What scientists are looking through the fossil record for is more information on how and when elephants developed their infrasonic call. Most of this research is based on inferences from comparisons of extinct” proboscidean”  structures and our living elephant forms.
p>From 55 million years of evolutionary data, we know that two or three species remain of the 164 elephant relations that lived in the past. The extinct forms ranged from deserts to mountaintops, on every continent except Australia and Antarctica. What scientists are looking through the fossil record for is more information on how and when elephants developed their infrasonic call. Most of this research is based on inferences from comparisons of extinct” proboscidean”  structures and our living elephant forms.

Riddle
Why do elephants have trunks?…..They have too much luggage for a glove compartment!

What to Do While Rose-Tu's Expecting

Posted by admin on June 1, 2012  |   No Comments »
Photo Credit (c) Oregon Zoo

Photo Credit (c) Oregon Zoo

While we watch the Oregon Zoo’s world-renowned elephant experts care for pregnant Asian elephant Rose-Tu (birth expected in late 2012), ThisWildLife.com thought some cool information about elephants would give animal lovers new insight while we wait. As human beings that weigh between 7 and 300 pounds, imagining the life of a 7,000-pound elephant described as “playful, spirited, and highly intelligent” will take some doing. Nevertheless, let’s give it a try, starting with the front—which is the trunk.

Smashing Pumpkins

Each fall, the Portland Zoo’s Asian elephants smash pumpkins in a public-pleasing ritual. Elephants crush the giant gourds with their feet. Once the fruit is open, trunks unfurl and each grabs a chunk of orange deliciousness. Not only does the trunk put food and water into an elephant’s mouth, but the trunk also houses two long nasal (trunkal?) passages that move air. The trunk manipulates objects, senses through touch and air-borne chemicals, creates sound, and disciplines members of the herd.

All About Trunks

Getting a perspective on this agile grabber with a long reach from a photograph is difficult. Here are the numbers: adults’ trunks vary from 6-12 feet in length and from more than 14 inches at it’s largest diameter, the trunk tapers to about 3 inches at the tip. Made mostly of muscle, elephants use their trunks to touch and investigate objects. The trunk’s well-developed muscles hold water or air inside and control the timing and force of the release. (Just ask an elephant keeper about this.)

In contrast to the power of the rest of the organ, the trunk tip is as sensitive and as agile as a finger in picking up small objects. At the zoo, you will see elephants use their trunk tips to gather dirt and then fling it onto their skin in a dry form of bathing. Elephants also use their trunks the way that submarines use periscopes, raising them over their heads.  The raised trunk samples the air for chemicals that excite the sensory cells lining the nasal passages. Scent is a major source of information for elephants about what is going on in their environment.

Trunks also allow elephants to create a variety of sounds. The same muscles that allow elephants to control the drawing of air and water into the trunk (and its release) also allows them to create a variety of sounds. (Think trombone.)  Elephants squeal in play, create a sound like a scream when angry, and trumpet warnings.  Sometimes when elephants are annoyed, they thump their trunk on the ground or an object.

Adult elephants use their trunks to protect young calves or discipline teenage elephants.  A mother uses her trunk to keep a curious calf from investigating something dangerous. Older females swat misbehaving younger females with their trunks.

More Information

The best learning about elephants is from observing them.  Check Oregon Zoo  for zoo hours.  Until you can get to the zoo, try this nifty Oregon Zoo video, The Squishing of the Squash 2011.

Scientists Plan to Resurrect Woolly Mammoth

Posted by admin on May 25, 2012  |   No Comments »

Japanese scientists have announced plans to clone the long-extinct woolly mammoth within five years, using DNA from the preserved hair of an animal.  The goal is to have an elephant carry the mammoth to term.  Get the details at Popular Science.