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Embryo: the egg after fertilization and before it has developed into a recognizable form.
Mammal: warm-blooded animal with fur.
Even human babies began in a special kind of egg without a shell.
Would you believe that you were once in an egg? During the earliest stage of development, animals grow inside an egg. This is true for insects, fish, birds, and for you. That’s right, even mammals (including people) have eggs. Nine months prior to our births, we all started out in a special type of egg that doesn’t have a shell.
Even though people don’t develop inside of an eggshell, many eggs do have shells. This helps keep the growing young (which are called “embryos” when they’re in eggs) protected from the world outside, while also making room for a bunch of food inside, kind of like the house you live in.
The eggs of birds, like these starling eggs, have hard shells.
The walls help protect embryos from the germs, predators, and temperature outside, and make some space inside to keep extra food. Eggs are well stocked with food because moms typically put yolk in their eggs or they send food into the eggs during development.
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Bibliographic details:
- Article: Don’t Judge an Egg by Its cover
- Author(s): Zachary Stahlschmidt
- Publisher: Arizona State University School of Life Sciences Ask A Biologist
- Site name: ASU - Ask A Biologist
- Date published: February 20, 2012
- Date accessed: April 17, 2024
- Link: https://askabiologist.asu.edu/don%E2%80%99t-judge-egg-its-cover
APA Style
Zachary Stahlschmidt. (2012, February 20). Don’t Judge an Egg by Its cover. ASU - Ask A Biologist. Retrieved April 17, 2024 from https://askabiologist.asu.edu/don%E2%80%99t-judge-egg-its-cover
Chicago Manual of Style
Zachary Stahlschmidt. "Don’t Judge an Egg by Its cover". ASU - Ask A Biologist. 20 February, 2012. https://askabiologist.asu.edu/don%E2%80%99t-judge-egg-its-cover
Zachary Stahlschmidt. "Don’t Judge an Egg by Its cover". ASU - Ask A Biologist. 20 Feb 2012. ASU - Ask A Biologist, Web. 17 Apr 2024. https://askabiologist.asu.edu/don%E2%80%99t-judge-egg-its-cover
MLA 2017 Style
A water python (Liasis fuscus) mom finds a nest and lays her eggs. Photo by Z. Stahlschmidt.
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