Education
The Permo-Triasic mammal-like reptile faunas of southern Africa, and the Jurassic mammalian faunas of Europe and North America, both discovered in the last century, have been central to the development of theories on the reptile-mammal transition.
In the more than 500 million year long history of vertebrates, mammals do not appear until quite late, some 225 million years ago.
The first mammals had come into a world dominated by reptiles. For one thing, reptiles are cold blooded, which means that their body temperatures changes with the temperature around them.
In contrast to reptiles, early mammals had the advantage of being warm-blooded. Because they have a constant body temperature regardless of their environment, mammals can compete with reptiles by remaining active throughout the night and throughout the year.
In early Triassic times, when Thrinaxodon was evolving in the direction of mammals, a new group of reptiles appeared on the scene; it was the dinosaurs or ‘ruling reptiles’ that came to dominate the animal world.
By late Triassic times, when the first mammals like Megazostrodon were scuttling around the undergrowth, large dinosaurs, such as Massospondylus were common. For the next 70 million years dinosaurs of every shape and size, from creatures no bigger than a domestic cat to the largest land animals the world has ever seen, took over the Earth.
Although the first Mezonoic mammal was discovered as early as 1764 in England, its significant was not understood until more than 100 years later, in 1871, when Sir Richard Owen (1804-1892) published his great opus, the ‘Monograph of the Fossil Mammalia in the Mezonoic Formations.’
The first mammals
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Education
The first mammals
The Permo-Triasic mammal-like reptile faunas of southern Africa, and the Jurassic mammalian faunas of Europe and North America, both discovered in the last century, have been central to the development of theories on the reptile-mammal transition.
In the more than 500 million year long history of vertebrates, mammals do not appear until quite late, some 225 million years ago.
The first mammals had come into a world dominated by reptiles. For one thing, reptiles are cold blooded, which means that their body temperatures changes with the temperature around them.
In contrast to reptiles, early mammals had the advantage of being warm-blooded. Because they have a constant body temperature regardless of their environment, mammals can compete with reptiles by remaining active throughout the night and throughout the year.
In early Triassic times, when Thrinaxodon was evolving in the direction of mammals, a new group of reptiles appeared on the scene; it was the dinosaurs or ‘ruling reptiles’ that came to dominate the animal world.
By late Triassic times, when the first mammals like Megazostrodon were scuttling around the undergrowth, large dinosaurs, such as Massospondylus were common. For the next 70 million years dinosaurs of every shape and size, from creatures no bigger than a domestic cat to the largest land animals the world has ever seen, took over the Earth.
Although the first Mezonoic mammal was discovered as early as 1764 in England, its significant was not understood until more than 100 years later, in 1871, when Sir Richard Owen (1804-1892) published his great opus, the ‘Monograph of the Fossil Mammalia in the Mezonoic Formations.’
The first mammals
- Iom Past Question With Answers For Mbbs Entrance Exam
See the most important entrance questions for mbbs ( medical) students :- 1. Immature proglotids of Taenia solium have: c) Vitelline follicles and shellgland but not glands d) Uterus but neither ovaries nor testes 2. Which one of the following insects...
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Question Option1 Option2 Option3 Option4 Answer Tapeworm has no digestive system because: it is a parasite it lives in intestine it doesn’t need food it absorbs its food from general body surface 4 Flatworms are devoid of: Circulatory...
- American Paleontologist, Simpson, George Gaylord (1902 – 1984)
Simpson, George Gaylord is United States paleontologist, whose work did much to shape the postwar development of paleontology and its impact on evolutionary. Simpson, born the son of lawyer on Chicago, Illinois, was educated at the University of Colorado...
- The History And Origin Of Mango
Native to northeast India, north western Myanmar and Bangladesh, they later spread to the rest of Asia by themselves and with the help of humans. The identification of a 65 million year old record of a leaf fossil belonging to the Mangifera in Meghalaya...
- William Harvey And The Circulation Of The Blood
William Harvey was born in Folkestone, Kent on 1 April 1578 to Thomas Harvey and his second wife Joan at a ‘faire built stone house’ known as the ‘Post House’. His father was a merchant. Harvey was educated at King's College, Canterbury In...