Did you ever wonder which are the largest mammals on Earth?

By David McClelland

In pre-historic times, there were some really huge dinosaurs. An example was the Argentinosaurus, a Sauropod. There is reliable evidence that they measured about 120 feet in length and weighed over 100 tons (over 200,000 pounds). No land animal comes close to being that large today.

Today, we know that elephants are the largest mammals on land and that whales are the largest sea creatures, but just how large are they?

Elephants are either from Africa, south of the Sahara, or from India and Southeast Asia.
African elephants are now the largest land animals and grow to a height of about13 feet high and 13,228 pounds or more than 6.6 tons.

Whales are even bigger. The blue whale is the largest. They grow to over 97.5 feet in length and weigh about 150 tons or about 300,000 pounds. And we thought elephants were big! A blue whale's heart weighs 1,300 pounds and beats at only about ten times each minute, whereas as human heart beats about 70 times per minute on average. The male's testicles are large enough for a small child to crawl through the major artieies.

Probably the most interesting feature of and elephant's body is its trunk. Asian elephants have one "finger" on the end of their trunks. African elephants have two "fingers." The scientific word for an elephant's trunk is proboscis. An elephant uses its trunk like a hand to put food into its mouth and to suck up water to squirt into its mouth or over its body to keep itself cool. Elephants also use their trunks like snorkels when crossing deep rivers.

Elephants are very intelligent and have the largest brains of all land animals. They are known to possess very good memories. They say that an elephant never forgets. Female elephants are called cows and they live with their calves and younger males, called bulls, in herds of 20 to 30. Older bulls usually live alone. Once a year, bulls go into a state called Musth (pronounced, 'must'), when male hormones make them very wild and dangerous. To find food in dry areas, herds may travel vast distances with the bigger elephants protecting the little ones between their legs.

When the leader of the heard senses danger, she lifts her trunk and sniffs the air – then warns the others by using her trunk to give a loud blast called a trumpet. If an intruder comes too close, she will roll down her trunk, throw back her ears, lower her head and charge at up to 50 mph. Elephants, males and females, usually live to about 70 years of age. When an elephant dies, its companions seem to mourn and cry.

Whales, dolphins and porpoises are mammals that are called cetaceans and live mostly in the seas and oceans. Dolphins and porpoises are small whales. Like all mammals, whales have lungs, which means they have to surface for air frequently, although they can remain submerged for up to 40 minutes. A sperm whale can hold its breath under water for 2 hours. Whales breathe through blow-holes on the tops of their heads. When the whale breathes out, it spouts out water, vapour and mucus. When it breathes in, it sucks in about 2,000 liters of air within about 2 seconds. Grey whales migrate farther than any other known animal, about 12,000 miles every year. Built-in GPS?

Like land animals, whales nurse their babies with their own milk. Whale milk is so rich that babies grow incredibly fast. Blue Whale babies are nearly 23 feet long at birth and gain an extra ton or so each day for the next year.

There are several groups of whales that have teeth and prey on large fish and seals. They are the sperm, beaked, belugas, narwhals, dolphins, porpoise and river dolphins. Whales keep in touch with sounds called phonations. Large baleen whales make sounds which are too low for humans to hear, but they can be heard by other whales for at least 50 miles. Now, how do you suppose man ever figured that out? The blue whale can whistle up to 188 decibels and they are the loudest animals on Earth.

That is a lot about elephants and whales, but I have just scratched the surface.