Stranger Than Fiction: Sea Monkey Science Information

The True Science page is always under construction as I learn more and more about our briny friends. Please see below for student resources, teachers’ resources, and other general information pages on Sea Monkeys. If you are interested in learning more about Sea Monkeys in space, please.

I am pleased to say that I have been able to get some actual Sea Monkey video on line! Finally! The videos are in windows media file format, so if you can’t play that, you can’t see these videos. I am working on getting them into other formats, but that costs money, and that might mean putting ads on the site…so you get the general idea. Also, please only download them once…my bandwidth is being sucked up quickly, and again we’re back to the whole money thing…
Click here to visit the Sea Monkey videos page now!

So what exactly are Sea Monkeys? Sea Monkeys are a type of brine shrimp, and a member of the animal family Crustacea, which also includes crabs and lobsters. All crustaceans have a hard shell (known as an exoskeleton) that provides their bodies with support, the way our bones help us keep our shapes. Having a hard shell is great when you’re a small creature in a big ocean! It makes it more difficult for animals to eat the Sea Monkey and get to its gooey parts inside. But there’s a
big problem. As the Sea Monkey grows bigger inside the shell, the shell stays the same size. So it needs to shed its shell, but this exposes its soft bodies to the outside world. It’s a perfect time for predators to eat them! (Fortunately, Sea Monkeys don’t have any predators in the little tank, so yours will be safe!) So they want to grow that shell quickly. Once the shell grows back, larger and harder, they are protected until the next time they need to grow bigger!
Have you ever wondered how Sea Monkeys can live so long in those little packages? Sea Monkeys can manufacture their own trehalose, a substance they use to coat their eggs to keep them safe from extreme temperatures and lack of water. Once coated, these eggs are now called cysts and they can live many years in this state. But once the conditions are just right and you add the water to the eggs, they come back to life! This is how
Sea Monkeys appear to come instantly to life when you add water!

Are your Sea Monkeys boys or girls? Is there a way to tell? Look at these two pictures….Do you notice any differences (other than the color)?


Female Sea Monkey


Male Sea Monkey

The males are always smaller than the females (although this doesn’t help if you don’t have any females to use as a comparison!) And if you look closely, you’ll see that the males have pincers coming from under their chins. They use these pincers the way crabs or lobster use their claws, to fight or grab things. The females are generally larger, and once mature, will carry a brown colored egg sac on their stomachs.

HOW WILL I KNOW WHEN THEY ARE FULL GROWN? Did you know that when Sea Monkeys are born, they have three eyes? And as they get older and closer to adulthood, they lose that middle eye? (And you’d think that something like that would come in handy!) This is one way to tell when they are full grown, although it is hard to see the third eye. There are other, easier ways to tell when Sea Monkeys are mature. First, they grow bigger — up to 3/4 of an inch long! Second, the males will grow pincers under their chins. Third, you will see an egg sac on the stomach of the female. And finally they will have moulted their shells quite a number of times. If you look on the bottom of the tank, you might see some black things that look like Sea Monkeys. These are discarded shells. Can you tell when they are moulting? It’s hard, but if you watch carefully, you may see them shedding their shells!

Sea Monkey Anatomy 101!

Sea Monkeys don’t have brains; they have groupings of nerves called “ganglia.” One of these is found in the Sea Monkey’s head, the other just below the gut. These ganglia send out the messages to the Sea Monkey’s body to do different things, such as eat, or sleep, or chase after another Sea Monkey.

They breathe through their legs, using long tubes that come up from their feet. The gill plates along the sides of their legs help transport the oxygen they need to live! This is why they are called “branchiopods”.

A Sea Monkey’s kidneys aren’t located in its abdomen, the way ours are. Its kidneys are located in its head!

Sea Monkeys have a circulatory system to help move the blood around their bodies. Their hearts, located dorsally in their torsos, pump blood around their tiny bodies, the way our blood is pumped through our circulatory systems. As a note, they have hemoglobin in their blood, as do we. Hemoglobin helps carry oxygen around the body. Strangely, there is an inverse correlation between the amount of oxygen in a Sea Monkey’s blood and the outside environment; the more oxygen in the tank, the less in the blood, and vice versa.

Sea Monkeys sometimes appear to be juggling the algae in the tank. Why is this? They are using their little legs to push the algae up to their mouth parts so they can eat it. And sometimes the Sea Monkey will look red. This is because the blue-green algae sometimes metabolizes their bodies to make it appear an orangy color.

Here follows a list of scientifically related Sea Monkey pages! Enjoy!

Science Project ideas
Please read these as opposed to writing to me for ideas. I simply don’t have any, and these sites will give you lots of ideas for creating science fair projects or science experiments. Please do contact me with your results, as I am collecting information for the book and for this site, and I would love to be able to include some successful ones!

Project ideas for students:

The Brine shrimp project
which is suitable for all age groups

The Silver stain Project which is more suitable for older grades and university

Where will brine shrimp hatch?”
(not sure of grade)

Sea Monkeys and salt Water experiments:
Finding optimal salt concentration for hatching brine shrimp

Project ideas for teachers:

Teachers: If you want more information on science projects or on the Bio-Mania grade appropriate Sea Monkey kits (for up to 6 students), then please write to The Sea Monkey Lady, Susan Barclay
for more information or click
here for Products for the Classroom!

The Brine Shrimp Fact Sheet from the Rhode Island Sea Grant provides a great summary of brine shrimp biology!

For some more sophisticated information on brine shrimp consult:

Sea Monkeys are a form of “Artemia Salina”, or brine shrimp. Sea Monkeys have been genetically altered to live longer, shed their shells more often, and live in a smaller, less briny tank. If you want more information, please search for “artemia salina” on the web.

I am in the process of amalgamating a great deal of material. Please keep checking back.