September 2005 Unknown

THIS MONTH'S WINNERS:

Our September mystery didn't fool too many people, at least among those who submitted. The three winners are:

Katherine Courtney
Teacher, Moorpark College

Thomas H. Milton
Teacher, Richard Bland College

Judy Isakovic
Teacher, University of Toronto

In addition to the prize winners above, the following people also correctly identified this month's unknown:

Steve Scott
Teacher, Lakes Community High School

Dr. William H. Le Grande
Teacher, University of Wisconsin- Stevens Point

Christine Dalton
Teacher, University College of the Fraser Valley

Don C. Smith
Student, Roanoke College

Julie Crawford
Position: Teacher, Mt Arlington High School

Thanks to all of those who submitted an entry to this contest.

Rockin' Rabbit - Rocky Mountain Pika, Ochontona princeps

If you've ever walked through alpine areas of the Rocky Mountains or Sierra Nevada Mountains, and heard a high-pictched 'eek' or 'neeat' sound coming from a boulder field, chances are you heard a pika (pronounced "PIE - kah"). Even better than hearing one, is seeing it. This little mammal has to be among the most lovable-looking animals on the planet. With their big eyes, short round ears, and plush fir, pikas are reminiscent of guinea pigs but they are not even closely related.

The pika is actually a close relative of the rabbits (Order Lagomorpha). This species, Ochontona princeps, is found in the Rocky Mountains, north to Jasper, Alberta. Pikas live in boulder fields, hiding out in spaces beneath rocks. They do not hibernate, but rather store dried grasses and other plant material, which they feed on through the winter under the heavy mountain snow loads. For obvious reasons, pikas are also called rock rabbits.

There is only one recognized genus, Ochontona, and there are probably 14 different species scattered in mountain ranges around the world. This kind of distribution supports one of the central ideas of evolution, that speciation usually occurs when populations become geographically isolated from a parent or ancestral population. In effect, the world's mountain ranges are like islands, (separated by large areas of land and water rather than seas), that act to prevent inter-breeding of populations. Over time, isolated populations develop distinct physical and/or behavioral characters of a new species as natural selection acts upon each isolated population.

Pikas live in loose colonies, but within the colony they tend to be territorial so that overcrowding and overuse of food resources is less likely. Like rabbits, pikas have the interesting habbit of refection (also known as coprophagy) - eating their own fecal pellets. For the pika, these morsels provide extra nutrition and energy that was not extracted on the first time through.

Like rabbits, pikas are prolific reproducers. They give birth in May to about 3-5 babies, and then may have a second or even third litter in the same summer. The babies are weaned after only 12 days.
 

For a concise and revealing teaching video about the the phylum to which pikas belong, get our video: Branches on the Tree of Life: Chordates or DVD, Branches on the Tree of Life: Chordates.