From birds to reptiles, insects to mammals, there are a surprising number of creatures that lay eggs in the animal kingdom. Most people have some knowledge of the eggs laid by chickens and other domesticated birds, but few realize the incredible diversity and complexity of egg-laying among different species. This article will look at the fascinating world of egg-laying animals, specifically at the various ways in which they care for their young.
What is Oviparous?
The term “oviparous” is used to describe animals that reproduce by laying eggs.
Some oviparous organisms allow their eggs to hatch on their own and don’t require any care from their parents, whereas other oviparous organisms make sure to take care of their eggs and don’t leave them until they’re ready to survive on their own without their parent’s assistance.
Animals that lay eggs
1. Insects
Insects are some of the most diverse and widespread creatures on earth, with over 900 thousand different kinds of living insects known. They’re available in a wide variety of shapes and sizes, ranging from extremely large moths to small fairyflies. Insects are considered cold-blooded, meaning that the temperature of their surroundings determines the temperature of their bodies.
Most insects reproduce by laying eggs, which later hatch into larvae. Some insects give birth to live young, but in either case, the larvae develop into adults through a process known as metamorphosis, in which they change form multiple times as they mature.
Monarch butterfly
Scientific Name: Danaus plexippus
Monarch butterflies are among the most well-known butterflies, with a native range that extends through much of North America. During the winter, they migrate from their breeding grounds in the northeastern part of North America to the forests in the southwestern part of Mexico.
These insects have been observed laying their eggs on milkweed plants. This will ensure that their caterpillars are able to consume milkweed leaves as soon as they hatch, allowing them to mature into healthy adult butterflies. Since they don’t take care of their eggs, the host plant provides all the nutrients that the developing larvae need.
Honeybee
Scientific Name: Apis mellifera
The Honey bees are insects that live in large colonies and are responsible for pollinating almost all flowering plants on earth. The queen bee is responsible for the reproduction of these lovely bees.
She does this by laying eggs within each cell of a honeycomb. The eggs that aren’t fertilized will hatch into males, known as drones, while eggs that are fertilized will develop into females.
Paper wasps
Scientific Name: Polistes carolina
The Paper wasps are social insects that build nests out of a paper-like material. One queen wasp lives in each wasp nest and is responsible for laying eggs in each cell.
After an average of three to five days, these eggs will hatch into larvae, eating partially digested insects until they mature. These wasps will mature into fully developed adults within three to four weeks.
2. Birds
Birds are among the group of animals that you can find in almost every part of the world. They’re a type of animal that can live on land, in water, and in the air.
You can recognize them by their wings, feathers, and beaks, all of which they use to eat food and drink water. Another characteristic of these creatures is the ability to reproduce by laying eggs, which later develop into young birds.
Depending on the species and the environments in which they live, birds lay their eggs in various locations. The size and color of these eggs can vary greatly from species to species.
Northern Cardinal
Scientific Name: Cardinalis cardinalis
The Northern Cardinal is a bird native to North America that stands out thanks to its vivid red plumage and distinctive red bill. Cardinals usually have a clutch size of two to five eggs, and the incubation period lasts one to two weeks.
The male helps out by bringing the female food and protecting the nest, but the female keeps the eggs warm. When the eggs hatch, the parents feed the young until they can care for themselves.
Wood duck
Scientific Name: Aix sponsa
The wood duck is a small and colorful duck that lives in North America. They usually live in water, preferably in places that have a mix of water and forests. The female wood duck will lay anywhere from six to sixteen eggs at a time, and she’ll do so in trees that are located close to bodies of water.
She tends to the eggs for about 30 days before they’re ready to hatch and emerge from the nest. Since wood ducks are precocial, these aquatic birds leave the nest as soon as they hatch, which is usually within 24 hours.
Blue jay
Scientific Name: Cyanocitta cristata
The Blue Jays are a species of bird known for their bright blue feathers and their intelligence. These birds lay eggs in nests that are built high up in trees.
They lay anywhere from 3 to 7 eggs at a time and incubate them for 16 to 18 days before the babies hatch. These eggs can be a variety of colors, including blue, green, or yellow, and both parents will care for their young until they’re old enough to leave the nest on their own.
3. Reptiles
Reptiles are creatures whose skin is protected by scales, which may be smooth or rough, depending on the species. These animals are cold-blooded, which means that they must rely on the sun’s heat to keep themselves warm because their internal body temperature depends on the heat they receive from outside sources or the environment they are in. One of the characteristics that all members of this group of animals share is the ability to produce young in the form of eggs.
There are more than 11,000 species of reptiles worldwide, so it’s easy to find one wherever you go. You’ll find that some reptiles prefer to live in arid environments, such as deserts, while others prefer aquatic environments, such as oceans or rivers, while still others prefer grasslands or forests.
American crocodile
Scientific Name: Crocodylus acutus
The American crocodile is a large reptile that lives primarily in mangrove swamps, river mouths, freshwater, and saltwater within its range. In the United States, this species of crocodilian can only be found in South Florida.
These creatures can lay anywhere from 20 to 60 eggs in a single clutch, which they then incubate for 85 days until the young hatch. They’ll typically lead the newly hatched crocodiles to the water, leaving them to fend for themselves.
Eastern box turtle
Scientific Name: Terrapene carolina carolina
The Eastern box turtle is a species of turtle that’s native to the eastern United States. The eggs of these creatures are incubated for three months in the leaf litter in which they were laid.
Temperature is the primary factor in determining the sex of the animal, and they usually lay 3 to 8 eggs per clutch. Incubating eggs between 72 and 81 degrees Fahrenheit will result in male offspring.
Green anole
Scientific Name: Anolis carolinensis
A green anole is a species of small, brightly colored lizard that’s native to the Southeastern region of the United States. They’ll lay anywhere from 15 to 18 eggs, which they’ll then bury underground in moist leaf litter or soil.
The eggs will take between five and seven weeks to hatch after being buried. Lizard mothers don’t provide any assistance to their young after they have been born, so the young lizards must learn to survive on their own.
4. Amphibians
Amphibians are a group of animals that include frogs, toads, salamanders, and newts. They all have the same characteristics, such as the necessity to live in a moist environment and the ability to take in air through their skin.
This group of animals also tends to lay eggs that are kept moist by a clear substance that looks like jelly. This is because amphibian eggs are more likely to dry out than those of other animal groups.
Their eggs will typically hatch into tadpoles, which will later develop into frogs or other amphibians once they reach adulthood. Most of these animals also grow webbed feet to support their movement in aquatic environments.
American Bullfrog
Scientific Name: Lithobates catesbeianus
The American Bullfrog is the largest species of frog found in North America, and the pools in which it lays its eggs are shallow and temporary. These tiny eggs are produced by females and can range from 12,000 up 20,000.
The males will then fertilize these eggs, and after a period of four days, they’ll hatch into tadpoles. It could also take tadpoles up to three years to mature into fully formed adults.
Eastern hellbender
Scientific Name: Cryptobranchus alleganiensis
One of the largest species of salamander found in the United States is called the eastern hellbender. This female hellbender lays anywhere from 150 to 450 eggs in the burrow that the males have prepared for her under some large rocks.
After the female has finished laying her eggs, the male will drive her away. The eggs will hatch into young hellbenders after 45 to 80 days, and these young hellbenders will mature into adults after 5 to 8 years.
5. Mammals
The term “mammal” refers to a group of animals that are distinguished by their ability to produce milk through their mammary glands for their young. They can be characterized by their more complex brains, furry skin, and the ability to perspire through their skin.
Compared to other groups of animals, these creatures are best known for giving birth to fully developed offspring. But there is a group of mammals known as monotremes that are able to lay eggs despite having mammary glands. The duck-billed platypus and the echidna are the only two remaining species of monotreme at this time.
Duck-billed platypus
Scientific Name: Ornithorhynchus anatinus
The duck-billed platypus is one of the few mammals in the world capable of reproducing by laying eggs. Typically, she’ll dig a burrow near the water’s edge and lay her two eggs inside.
It’ll take the female platypus ten days to incubate the eggs, and once the young have hatched, the female platypus will feed them the milk that she produces. As the young become adults, she’ll eventually give them more freedom to forage independently.
Echidna
Scientific Name: Tachyglossus aculeatus
The echidna is a small, egg-laying mammal native to Australia. About once a year, the female will lay eggs, which she’ll then carry in her pouch until they’re ready to hatch.
After 10 or 11 days, the eggs will hatch, and the mother will begin feeding the young her milk. This process will continue for between 150 and 200 days. They’ll then reach adulthood between the ages of three and five years.
6. Mollusk
Mollusks are a diverse group of invertebrate animals that include snails, clams, octopuses, and squid. They are characterized by their soft bodies, which are often enclosed in a hard shell, and their ability to lay eggs.
Most mollusks reproduce sexually, with males and females releasing sperm and eggs into the water, but some species lay eggs directly on the seafloor or attach them to rocks or other surfaces. Examples of mollusk species that lay eggs include the common whelk and the giant clam.
Common whelk
The common whelk, also known as the waved whelk, is a predatory snail found in the Atlantic Ocean. It has a spiral-shaped shell that can grow up to 5 inches long and is typically gray or tan in color. One notable aspect of the common whelk’s reproductive behavior is its ability to lay egg capsules on rocks or other hard surfaces.
These capsules contain dozens of small eggs and resemble a coiled rope or strand of beads. The eggs hatch into larvae that eventually settle on the seafloor and develop into adult whelks.
Squid
Squids are a type of cephalopod mollusk found in oceans worldwide. They have elongated bodies, eight arms, and two longer tentacles equipped with suckers for capturing prey. Squids are known for their ability to swim quickly and change color to blend in with their surroundings.
One notable aspect of squid reproductive behavior is their use of egg masses to lay eggs. After mating, female squid will lay hundreds of small eggs in a gelatinous mass that can be several feet long. The egg mass is typically anchored to the seafloor or other surfaces and left to develop and hatch on its own.
Louise writes about a wide variety of topics including wildlife, animals, and nature. She’s developed a growing interest in animal biology and categorization due to her fascination with how they interact with one another and with their surroundings.