Animal Encyclopedia With Facts, Pictures, Definitions, and More!

Once the dominant land vertebrates on the planet, reptiles still occupy just about every single ecosystem outside of the extreme north and south. Animals dominate human conceptions of life on Earth not simply by their size, abundance, and sheer diversity but also by their mobility, a trait that humans share. So integral is movement to the conception of animals that sponges, which lack muscle tissues, were long considered to be plants. Only after their small movements were noticed in 1765 did the animal nature of sponges slowly come to be recognized. Animals are multicellular eukaryotes whose cells are bound together by collagen. Animals dominate human conceptions of life on Earth because of their size, diversity, abundance, and mobility.

Reptile Species

Check out the animals we recently added to our Animal Facts page. Birds are feathered, egg-laying vertebrates, most of which are able to fly. They are found on every continent and are able to survive in a wide range of conditions. The group includes fish such as trout, goldfish, cod and marlin. The world’s oceans are home to a greater number of mollusk species than to species of any other animal group. Many crustaceans have a carapace (hard shell), which is part of the exoskeleton.

Shark tagged from submarine for first time in history

The most common pets include dogs, cats, fish, and birds, but there are also many amazing exotic pets like reptiles, lizards, and more! Unlike invertebrates, vertebrates (members of the subphylum Vertebrata) form a scientific group in animal classification. Animal Pedia is a growing digital encyclopedia that brings the animal kingdom to life, currently featuring an extensive collection of reptiles species. We offer comprehensive species profiles and clear scientific insights into biodiversity, and ecology. Perfect for wildlife enthusiasts, students, researchers or even casual learners, Animal Pedia makes learning about animals engaging and accessible.

What are the basic functional systems of animals?

Though other animals only live on land or in the water, amphibians have the unique ability animal spirits to thrive equally in both. Amphibians cover over 6,000 different species across the globe, but about 90% are frogs. Animals first appeared in the fossil record in the late Cryogenian period and diversified in the subsequent Ediacaran period in what is known as the Avalon explosion.

• Although all animals share the above characteristics, animals exhibit diverse body plans, life cycles, and forms of behavior.
• Animal classification provides a structured way to name, rank, and classify the millions of animal species discovered.
• Historically, Aristotle divided animals into those with blood and those without.
• This is largely because animals have developed muscles and hence mobility, a characteristic that has stimulated the further development of tissues and organ systems.
• Animals dominate human conceptions of life on Earth because of their size, diversity, abundance, and mobility.

Lancelets are small fish-like animals with translucent bodies. Although they don’t have a backbone – and are therefore not vertebrates – they do possess a flexible central nerve cord called a notochord. Animal classification is the scientific system used to categorize and organize the vast diversity of animals on Earth. Animals have evolved to live in a wide variety of habitats. On the pages below, you can explore various habitats and the animals found in each. See lists of animals that start with every letter of the alphabet, from A to Z.

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• A pet is a domesticated animal that lives with a person or family, usually in a house.
• Once the dominant land vertebrates on the planet, reptiles still occupy just about every single ecosystem outside of the extreme north and south.
• Animals follow virtually every known mode of living that has been described for the creatures of Earth.
• Chihuahuas are the smallest, and were likely bred for companionship or to hunt small rodents.

More than half are passerines, or “perching birds”, members of the order Passeriformes. Passerine feet have three forward-facing toes and one backward-facing toe, an arrangement favorable to perching. Most mollusks live in the sea, but some, such as snails and slugs, are also found on land. In order to be placed in the animal kingdom, rather than another kingdom, an organism must have certain characteristics, which are listed in the following section.

Common to all living animals, 6,331 groups of genes have been identified that may have arisen from a single common ancestor that lived about 650 Mya during the Cryogenian period. Most people know that crabs are crustaceans, but the group contains many other types of animals, including lobsters, shrimps, krill and water fleas. Most crustaceans live in the sea, but some, such as woodlice, are adapted to living on land. In size animals are outdone on land by plants, among whose foliage they may often hide.

MAMMALS

While invertebrates exhibit a wide range of body plans and structures, vertebrates have a more standardized body plan due to their shared backbone structure. By comparing traits and genetic sequences, scientists can infer these evolutionary relationships and construct phylogenetic trees, diagrams that depict the inferred evolutionary relationships. Such analyses have greatly advanced our understanding of animal biodiversity and the evolutionary history of life on Earth. However, plant cells have certain features, such as a rigid cell wall and chloroplasts (which enable photosynthesis) that are not present in animal cells. Animals range from relatively simple organisms such as sponges and jellyfish to complex ones such as humans and elephants. From the smallest insects to the largest whales, deep sea fish to high-flying birds; animals come in many different shapes and sizes and are found in nearly every part of the world.

Timber Rattlesnakes: Venomous and Elusive – Species Guide

Fish are aquatic animals with streamlined bodies, fins instead of limbs, and gills. Gills are organs that extract oxygen from the water and excrete carbon dioxide. Vertebrata is home to all fish, amphibians, reptiles, mammals and birds. They are also studied by scientists for clues as to how vertebrates (animals with backbones) evolved.

Animal Pedia is a leading online website offering a vast library of information on animals from all corners of the globe. Discover our newest additions to the animal kingdom database. Then test your knowledge with our fun, free Animal Quizzes! You can also download free coloring pages, word searches, and animal mazes on our Activity Sheets page.

Like mammals, birds are warm-blooded vertebrates with four-chambered hearts. However, they are more closely related to reptiles and are believed to have evolved from dinosaurs. Historically, Aristotle divided animals into those with blood and those without.