What Did Turtles Evolve From?
The development of turtles began millions of years ago as part of animal evolution. Turtles are an egg-laying group of animals called Reptiles, having a flat and solid shell that covers their body and limbs. Turtles are classified within the Order Testudinales belonging to the Class Reptilia that includes Snakes, Lizards and Crocodiles.
An Overview of Turtle Evolution
Turtles evolved from early reptilian ancestors that lived some 220 million years ago. Their ancestors were Diapsids, two-legged creatures that were the common ancestors of modern lizards and snakes. The earliest turtles evolved during the Triassic Period, when they developed a unique feature: bony plates which covered their bodies as a protective armor.
Every Turtle Has Its Own Shell
The most defining feature of the turtle is its shell. Turtles have a bony layer called a carapace that covers its back and sides. This layer is made up of scutes which are connected to the ribs as well as to each other. The scutes are made of bone and covered with a horny layer which can be scaly, glossy, or rough depending on the species. Beneath the carapace is the plastron which is a diamond-shaped bone structure that shields the belly of the turtle.
Types of Turtles
Turtles come in many different shapes, sizes, and colors. They can be aquatic, terrestrial, or semi-aquatic. There are more than 300 living turtle species that can be separated into two groups:
- Tortoises: Land-dwelling turtles with thick and heavy shells.
- Aquatic Turtles: Water-dwelling turtles such as sea turtles and fresh-water turtles.
Turtles have evolved from their Diapsid ancestral reptiles to become the modern shape and form that we recognize today. Every turtle has its own unique shell that functions to protect its body and provide it with mobility in its environment. Turtles come in many different shapes, sizes, and colors and they can be classified into two main groups: tortoises, and aquatic turtles.
Turtles are an amazing and unique part of the animal kingdom and we can learn a lot about how they’ve evolved over the years.