Turtles and Tortoises may look alike to most people, but they are quite different from each other.
Turtles typically live in or near water. They like to swim, and are mainly Carnivores (meat eaters) with their diet consisting mainly of fish, worms and insects. Some turtles (like Box Turtles) are Omnivores (meat and plant eaters, like us). Tortoises on the other hand live on dry land. While different Tortoises have different diets, they are all herbivores (plant eaters).
One way to tell the difference between a Turtle and a Tortoise is the shape of the shell. Most Tortoises have a high-domed shell, and contoured segments (that is to say that the shell segments are raised to a degree). Turtles on the other hand typically have flatter, smoother shells that make it easier for them to swim in water. As with most rules, there are a few exceptions like pancake tortoises that have flattened shells even though they are a type of Tortoise, and Box Turtles (which are quite common) who have high-domed shells even though they are a type of turtle.
Another common difference is the eyes. Turtles have visible irises (the colored part of the eye) where as most tortoises have black irises that blend in with the pupil. This can be especially useful when identifying box turtles since their shell is deceivingly dome-shaped as mentioned above. Once again, there is an exception; Desert Tortoises have white irises even though they are a type of Tortoise.
The last noticeable difference is the shape of the feet. Turtles (except Box turtles once again) have webbed flipper-type feet for swimming. If you look at a Tortoises back feet, they look more like an elephants (pillar ending in a stub).
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