1.A disaster about 65 million years ago killed off the dinosaurs and many other creatures.
The main new group of animals was the mammals. Most were small, like rats and mice. Leptictidium lived 50 to 40 million years ago. It may be related to moles and shrews.
V Leptictidium probably hopped like a kangaroo! V
2.Whales began life on dry land and gradually returned to the sea. Pakicetus lived about 50 million years ago and was nearly 2 meters long.
It probably spent a lot of time on land as well as in water.
V Pakicetus is the earliest-known whale. V
3.Often the name of a prehistoric animal can be misleading, like Palaeotherium, which simply means 'ancient animal'.
However, this name was given over 200 years ago, in 1804 because scientists of the time did not know as much as modern scientists. Later studies show that Palaeotherium was one of the first animals in the group of hoofed mammals that includes horses.
V A picture of a Palaeotherium. V
4.Around 40 million years ago, the largest animal walking the Earth was Uintatherium.
This plant eater was over 3 meters long and nearly 2 meters tall at the shoulder about the same size as a cow. Its fossils were found near the U into River in Colorado, USA. Uintatherium is thought to be a cousin of horses and elephants.
V A mother Uintatherium and her baby. This strange-looking creature was the largest land animal of its time. Its head was covered in horns and it had small tusks. V
5.An animal's looks can be misleading.
Patriofelis means 'father of the cats'. It lived 45 million years ago and was named because scientists thought it looked like an early cat. Later they realized it was really a member of an extinct group of hunting animals called creodonts.
V A photo of a Patriofelis. V
大约六千五百万年前的一场灾难杀死了恐龙和许多其他的生物。
主要的新动物群是哺乳动物。大多数是小的，像老鼠和老鼠。 Leptictidium生活在50至4000万年前。它可能与痣和be be有关。
V Leptictidium可能跳起来像一个袋鼠！ V
冬天在旱地开始生活，逐渐返回海里。 Pakicetus生活在大约5000万年前，长约2米。
它可能花了很多时间在陆地和水中。
巴基斯坦是最早知名的鲸鱼。 V
通常，史前动物的名字可能是误导性的，如古老的古老动物，简称“古代动物”。
然而，这个名字是在二千多年前，1804年，因为当时的科学家不像现代科学家那么多。后来的研究表明，古生物是包括马在内的蹄类哺乳动物的第一动物之一。
V古老的照片。 V
四千万年前，走在地球上的最大的动物是Uintatherium。
这个植物食者长三米多，身高近二米，肩高，大小与牛一样。它的化石在美国科罗拉多州的U附近被发现。 Uintatherium被认为是马和大象的表弟。
母亲Uintatherium和她的宝宝。这个奇怪的生物是当时最大的土地动物。它的头被喇叭覆盖，它有小象牙。 V
动物的外观可能会误导。
Patriofelis是“猫之父”。它住在4500万年前，因为科学家认为它看起来像是一只早期的猫。后来他们意识到这真的是一个绝种的狩猎动物小组的成员，叫做creodonts。
V Patriofelis的照片。 V