The new Time Tunnel at the Yakima Valley Museum provides a glimpse of the Yakima Valley 10,000 to 25 million years ago. This was when our present local landscape was formed in a drama of lava flows and great glacial floods. Fossils hidden beneath our feet help reveal the unique animals which lived in the Yakima Valley during those years; mastodons, mammoths, giant camels, tiny horses, huge bison, and even a giant ground sloth. See the Time Tunnel In QuicktimeVR (Click here)

Plans began in late 1995 for an exhibition that would tell this story using the museum's collection of fossil animal bones as well as provide opportunities for new educational programs in the nearby Children's Underground hands-on exploration center. With the help of the Kiwanis Club of Yakima and the Yakima Kiwanis Charitable Trust, the development of the Time Tunnel was officially underway in 1996.

"Children visiting the museum and Children's Underground often expect to see dinosaur bones" explained David Lynx, Curator of Education. However, when dinosaurs roamed the earth Yakima was underwater, a bay of the Pacific Ocean. No dinosaurs lived here. So Lynx decided that this exhibit would highlight this area's prehistoric past above water; the Pleistocene, when such ice age animals as the mammoth lived in Yakima, and the even earlier Miocene, when central Washington was moist and "tropical" and home to even stranger beasts.

The new exhibit will feature scale models and real bones of prehistoric animals. Giant photos and interactive maps show how the Columbia Plateau was heaved up in a firey flood of lava and how an inland sea drained its raging waters across Washington in the devastating Missoula Floods which carved out the Columbia Gorge.
 

Mammoth Although the Yakima area mammoth species has not been clearly identified, it is thought to be similar to the Columbia mammoth. The Richland mammoth is a dwarf species. The word Mammut, meaning earth burrower, can be traced back to the Middle Ages, when eastern European farmers found the gigantic bones in their fields and believed that they belonged to monstrous burrowing beasts. Elephants congregate at water sources in dry seasons, and a drought year effectively limits their movements to remaining water refuges. An extended hard freeze or lack of snow cover during late Pleistocene winters would have had the same effect on mammoths that hot droughts have on modern elephants. The affected mammoths would have sought open water in warm springs or would have tried to break stream or pond ice to reach the unfrozen water below it. And because all elephants need considerable amounts of moisture daily, taken in the form of water or derived from their solid food, in times of water shortages elephants can quickly weaken and become highly vulnerable to predation. Adult mammoths stood between about 10-12 feet at the shoulder and weighted between 6-8 tons.

Mastodon The mastodon names means nipple tooth, which describes the large, low cusps arranged opposite one another forming low ridges separated by open valleys. The Mastodon was known to live in valleys, lowlands, and swamps. The mastodon was shorter than its cousin the mammoth, approximately 10 feet tall at the shoulder. The mastodon was a vegetarian that ate grasses, leaves, and a variety of dry land and water plants. They reached North America during the Middle Miocene, about 15 million years ago.

Bison latifons The largest species of bison known, along with other species of bison, immigrated to North America via the Bering land bridge from Asia. Its size helped it to compete with other large herbivores of the Pleistocene, in a land where food was growing scarce. Adapted to forest openings and woodlands it was large bodied, long legged and had large horns which spread about 3 feet from tip to tip. It survived into the late Pleistocene, and possibly interbred with a more modern bison that did survive into the Holocene or it gradually reduced in size over time.

Plesippus The modern horse we have in Yakima is a transplant from Europe. The Plesippus is a horse only 13 hands high. Evidence for horses has been found in Ellensburg Formation. This species had side-toes which tended to become further reduced and finally were lost. In some populations there would be individuals having vestigial side toes living together with individuals in which the toes were absent and only the splint bones remained, as in modern horses. Known from the Eocene of both North America and Europe, horses subsequently became extinct in Europe during the Oligocene but persisted in North America, and evolved. During the Miocene, three-toed horses dispersed form North America into Eurasia and Africa. Several times during the Pliocene and Pleistocene, one-toed horses migrated into Eurasia, Africa, and south America. Once horses became extinct in North America at the end of the Pleistocene they where reintroduced in America by the Spanish.

Megalonyx Originating in South America during the Oligocene, then migrating to spread across North America during the Miocene the ground sloth survived until 10,000 years ago (Pleistocene). Evidence for Megalonyx rohrmanni has been found in the Ringold Formation. Megalonyx ate trees and shrubs standing on its hind legs, giving it the height of six feet, and allowing it to reach the best leaves and twigs. Unlike modern sloths, which spend most of their time in trees, these sloths spent most of their time on the ground.

Megatylopus A possible cousin to camelops, this giant camel lived in the Miocene and Pliocene period. Evidence of megatylopus has been found in the Ringold Formation. The camel family evolved in North America, later migrating to Eurasia, Africa, and South America (llamas). Megatylopus is the geologically oldest of the giant Camelini (Camel). Most of the camelids were grazers and traveled in herds. It became extinct in North America at the end of the Pleistocene.