Do tortoises descend from dinosaurs?

Recent studies have shown that turtles belong in the group Archelosauria, along with relatives like birds, crocodiles, and – you guessed it – dinosaurs. Turtles evolved alongside dinosaurs, with sea turtles emerging as a distinct type about 110 million years ago.

How did Galapagos tortoises evolve?

All species of Galápagos tortoises evolved from common ancestors that arrived from mainland South America by overwater dispersal. Genetic studies have shown that the Chaco tortoise of Argentina and Paraguay is their closest living relative.

Why did giant tortoises evolve?

Evolutionary history. All species of Galápagos tortoises evolved from common ancestors that arrived from mainland South America by overwater dispersal. Genetic studies have shown that the Chaco tortoise of Argentina and Paraguay is their closest living relative.

Why did turtle shells evolve?

It has long been thought that the tough, bony shells of turtles and their ancestors are formed from their ribs. Becoming heavily modified over millions of years, they joined together to form the tough, protective armour that we know and love so much about modern turtles.

How did the turtle shell evolve?

In turtles, the ribs and vertebrae grow into the outer skin layers and connect together like tectonic plates, forming a solid shell. The earliest known turtles stretch back in time to the Triassic period, around 240 million years ago, and perhaps even further.

How does a tortoise got its shell?

Several researchers suggested that bony plates embedded in the skin, called osteoderms, which are found in crocodilians and some other reptiles, had fused to the underlying bones of the turtle to form a solid bony shell.

What is the habitat of a tortoise?

Tortoises are a group of terrestrial turtles globally distributed in habitats ranging from deserts to forests, and include species such as the Greek and the Galapagos tortoises. Some species evolved large body sizes with a shell length exceeding one metre, whereas others are no larger than six to eight centimetres.

Did giant tortoises evolve on islands?

The evolution of giant tortoises might not be linked to islands, as has previously been thought. In a first-of-its-kind study, researchers from Argentina and Germany have presented the most comprehensive family tree of extinct and extant tortoises so far.

What can we learn from tortoise fossils about body size evolution?

The researchers analysed genetic data from living species together with osteological data from fossil and living tortoises. This is the first global-scale study to investigate body size evolution in tortoises. The fossils reveal a very different picture of the past compared to the present.

Where are the Galapagos tortoises from?

The Galapagos islands are a chain of volcanic islands off the coast of Ecuador. Evolution of Tortoise Shapes. Galapagos tortoises have two very different shapes, each adapted for different feeding habits needed on low, arid islands versus high, lusher islands.