At the Science Mill, our focus is bringing STEM - Science, Technology, Engineering, and Math - to life. One of our favorite ways to do this is through living exhibits, like our odd little axolotls and our aquaponics greenhouse. We are also home to some pretty adorable tortoises!

The African Spurred Tortoise exhibit is a great place to focus on biology disciplines, including zoology and life sciences. Visitors get an up-close look at these gentle giants in their outdoor tortoise habitat. Weekend visitors to the Science Mill are invited to join us for our Tortoise Talks to learn more about what they eat and how they behave.

On March 25, 2019, one of the Science Mill’s African Spurred Tortoises, Tortilla, laid a clutch of 24 eggs, which Science Mill biologists dug up and placed in an incubator to protect them from predators. Over the following months, the eggs were observed for signs of development. Not all eggs were viable, but we’re thrilled to report that after 106 days in the incubator, six eggs hatched between July 9 and 12. Weighing in between 29-36 grams each, these tiny tortoises will grow quickly, eventually weighing over 100 pounds when they are adults (the males could even break 200 pounds!).

These fascinating animals are the only animals that have both a shell and a backbone, but that’s just one of many cool tortoise facts. Did you know…

• They are the largest mainland tortoise species, and only island tortoises from Aldabra and Galápagos are bigger.

• What makes it a tortoise, and not a turtle? According the San Diego Zoo, “It depends on who you ask or where you are in the world, but most people recognize tortoises as terrestrial or land-loving with stubby feet (better for digging than swimming) and a heavy, dome-shaped carapace. Aquatic and semi-aquatic turtles are known as just that, turtles. Turtles tend to have more webbed feet (but not always) and their shells are more flat and streamlined.”

• They are native to the the scrub and grassland found south of the Saharan desert.

• Tortoise shells are made of keratin, like our fingernails. They can feel pressure and pain through them.

• African Spurred Tortoises can live over 100 years if provided with proper dietary needs and husbandry (the science of breeding and caring for animals).

• Speaking of diet, they are herbivores. It is important to offer them a high fiber diet, such as grasses and leaves, in captivity. Too many fruits and veggies can upset their digestive tract.

• At the Science Mill, we feed our tortoises a variety of lettuces, spinach, bramble, sorrel, and leaves from fruiting plants such as papaya, cucumber, and pumpkin.

• About 2 months after mating females will dig a nest and will normally lay about 15-30 eggs. Eggs will typically incubate for 100-120 days before hatching.

• Baby tortoises are about the size of ping pong balls when they hatch out of their eggs by using a specialized egg tooth that drops off shortly after hatching. What a cool tool!

The Science Mill got to see these egg teeth in action when we welcomed our baby African Spurred Tortoises to our family this summer.

Babies as special as these deserve names just as unique, and we need your help choosing the perfect names. Please vote for your favorite name today!