Eggs-travaganza with Happy Dancing Turtle During the spring, we can observe the young of many wildlife species! Animals can be split into two major groups when it comes to babies. Viviparous animals, like humans, develop young inside the parent and give live birth. Oviparous animals, like birds, lay eggs and the young develop inside the eggs before hatching.
Scientists estimate that about 99% of animals hatch out of eggs! Wow! How can that be? Well, most of the animals in the world are insects, and most insects hatch from eggs! Many of the animals we're most familiar with are vertebrates, meaning they have a back bone. There are five major groups of vertebrates. The "general rule" is mammals give live birth and the others lay eggs, but let's see if that's true! Can you name some animals in each group?!
1. Mammals - Almost every mammal gives live birth (except the platypus and the echidna). 2. Reptiles - Most lay eggs, but there are numerous snakes and lizards that give live birth. 3. Fish - A very small percentage of fish are known to give live birth, including some sharks! Most fish lay eggs. 4. Amphibians - Almost all lay eggs, but there are a handful of frogs that have recently been discovered to give live birth! 5. Birds - All species of birds lay eggs.
Spend some time brainstorming what other traits fit each animal group!! (Example: think fur, scales, feathers; how they move, breathe, grow; where they live; warm vs. cold blooded; etc. Eggs can come in all different forms! They come in all different colors, patterns, and textures. Some are bright blue, some are speckled and camouflage with their surroundings, some are hard, and some are soft or gooey! They can be laid in the water, underground, or in a nest.
Learn more about eggs with the activities and science experiments on the next pages!
Happy Dancing Turtle is planning a public Spring Egg Hunt in mid-April, giving families something to do outside while learning more about egg-laying animals! Details will be posted on Facebook at www.facebook.com/HDTDriftlessRegion The Eggs-traordinary Egg Humans eat chicken eggs and often use them in cooking/baking (unless you're allergic). Let's take a closer look at the chicken egg! Parents: use the text below to explain each part as you find it in your egg!
a bowl
Eggshell: hard protective covering, but gasses (like oxygen) can get through the eggshell! Shell Membranes (inner & outer): help protect the egg from bacteria & prevent moisture from leaving the egg too quickly. Air cell: forms at the large end of the egg, chicks use before hatching. Albumen: the liquid where the embryo develops, has protein necessary for development. Chalazae(plural): made from special proteins, these twisted cords can be seen in very fresh eggs and help hold the yolk in place. Yolk: contains vitamins, minerals, & fat, is a food source for the developing embryo (if fertilized & growing a baby chick). Germ-Spot: white spot on the egg where the hen's DNA is stored (if fertilized, both male & female genetic material). More Eggs-tra Fun Activities! Make A Reptile Egg! Bird eggs are typically laid in a nest and have a hard shell to protect them from the environment. This hard shell & the membranes inside also helps keep moisture inside the egg so it doesn't dry out! Reptiles, like snakes or crocodiles, typically lay their eggs underground, where they are not as likely to dry out. Their shell feels a little bit like leather. Amphibians, like frogs, and fish lay their eggs in the water and they feel really gooey, kind of like a waterbead! Let's make a reptile egg to see how it feels.
Materials: 1 Egg, uncooked without cracks White vinegar Spoon Bowl or cup - clear containers work best, as it is easier to see!
Instructions: Place an unboiled egg into a container of vinegar. Observe what happens when you place the egg in the vinegar. What do you see? Eggshells are made from calcium carbonate, which dissolves in weak acids, like vinegar! The bubbles are a sign a chemical reaction is taking place. Put your egg somewhere out of the way where it won't be bumped. Continue to periodically check on your egg and make observations. After 24 hours, you can gently drain the vinegar from the container, and replace with fresh vinegar. It *may* help speed up the process. Continue to observe your egg until it looks like all of your shell has dissolved (2-3 days) When the shell appears to be gone, gently (they can break!) scoop your egg out of the vinegar using the spoon. How does it feel? Your now "naked" egg has a similar texture to the leathery eggs of reptiles.
Eggs-tra Steps! Does your rubbery egg bounce? Try gently dropping it from about 1 inch above a surface. Did it bounce? Try dropping it from slightly higher and higher, increasing at about half an inch per drop. What height does it finally break at? (Be prepared for a bit of a mess when it breaks! Remember to carefully clean up raw egg!!) Your rubbery egg lets liquid in and out through the membrane. If you put your egg in a cup of water, it will actually grow! The water content inside of an egg is about 90%, so when it's placed into a cup of 100% water, water will enter through the egg's membrane due to a process called osmosis!
More Egg Activities DIY Eggshell Geodes (search online for directions) Can you blow a hard boiled egg out of the shell?! (Look for video tutorials) Make Your Own Nest! Collect natural materials from your yard to create your own nest! Sticks, twigs, dried plant materials, & even mud! Can you do it without glue? Birds don't get glue, how do they do it? Camouflage Eggs Many animals rely on camouflage to help keep their nest and eggs safe! Can you color these eggs to help them camouflage? Camouflage Eggs Many animals rely on camouflage to help keep their nest and eggs safe! Can you design your own egg pattern to camouflage somewhere in your house or yard?