Animals

Eastern lowland gorilla (Grauer's gorilla) Eastern lowland gorilla Subspecies of eastern gorilla native to eastern Democratic Republic of the Congo, notable for its size, social behavior, habitat, and critical conservation status.

Eastern quoll (Dasyurus viverrinus) Eastern quoll A small spotted carnivorous marsupial native to Tasmania. The eastern quoll is nocturnal, insectivorous and carnivorous, and is the focus of conservation and reintroduction discuss…

Eastern wallaroo (Macropus robustus): description, habitat, and ecology Eastern wallaroo The eastern wallaroo (Macropus robustus) is a robust Australian macropod found mainly along the Great Dividing Range. This article summarizes its appearance, behaviour, range, subs…

Echidna — the spiny anteater of Australia and New Guinea Echidna Echidnas are egg-laying mammals (monotremes) covered in spines, native to Australia and New Guinea. They feed on ants and termites, have unique reproductive traits, and play roles…

Echinoderm Echinoderms are a phylum of exclusively marine invertebrates—sea stars, sea urchins and relatives—characterized by calcitic plates, a water‑vascular system and usually fivefold sym…

Echinodon — a small heterodontosaurian dinosaur genus Echinodon Echinodon is a small heterodontosaurian ornithischian known from fragmentary jaws and teeth in Early (Lower) Cretaceous Europe; noted for varied tooth shapes and a debated position…

Echis — saw‑scaled vipers (venomous snakes of dry regions) Echis Echis is a genus of small to medium venomous vipers known as saw‑scaled or carpet vipers, widespread across Africa, the Middle East and South Asia and notable for their medically i…

Echiura (spoon worms): unsegmented marine worms and their biology Echiura Echiura, or spoon worms, are unsegmented marine worms long treated as a distinct group but now placed with annelids by molecular studies. Overview of anatomy, life cycle, ecology a…

Edaphosaurus — the sail‑backed early synapsid Edaphosaurus Edaphosaurus was a bulky, sail‑backed pelycosaur from the Late Carboniferous to Early Permian, notable for its distinctive knobbed neural spines, herbivorous adaptations, and fossi…

Edible dormouse (Glis glis): overview, behaviour, history and human interactions Edible dormouse Comprehensive encyclopedia entry on the edible dormouse (Glis glis): appearance, behaviour, diet, hibernation, distribution, human uses from Roman times to modern management, intro…

Edible frog (Pelophylax kl. esculentus) Edible frog A European hybrid frog commonly called the edible, water, or green frog; notable for its hybrid reproductive system, widespread wetland habitat, and use as a culinary ingredient in…

Edmontonia: armored nodosaur of the Late Cretaceous Edmontonia Edmontonia was a heavy, low-slung nodosaurid dinosaur from the Upper Cretaceous of western North America, known for its bony plates, rows of spikes and prominent shoulder spines us…

Edmontosaurus — Late Cretaceous duck‑billed hadrosaur Edmontosaurus Edmontosaurus is a well‑known North American hadrosaur from the latest Cretaceous, noted for its broad toothless beak, massive dental batteries, frequent fossils and rare mummified…

Eel (Anguilliformes): appearance, life cycle, habitats, and human interactions Eel Long, snake-like teleost fishes (order Anguilliformes) with distinctive life cycles. Article covers anatomy, larval stages, habitats from shallow rivers to deep sea, uses, and nota…

Egyptian cobra (Naja haje) Egyptian cobra A large venomous cobra native to North Africa and parts of the Middle East, known for its hood, medical significance, and role in ancient Egyptian symbolism.

Egyptian fruit bat (Rousettus aegyptiacus) Egyptian fruit bat A medium-sized Old World fruit bat found across Africa and the Middle East; frugivorous, cave-roosting, notable for tongue-click echolocation and roles in pollination, seed dispers…

Egyptian vulture (Neophron percnopterus) Egyptian vulture Small Old World vulture known for white plumage, scavenging diet and rare tool use; breeds across southern Europe, Africa and Asia and faces major conservation threats.

Ekaltadeta — extinct Australian giant rat-kangaroo Ekaltadeta Ekaltadeta, an extinct genus of large rat-kangaroo–like marsupials from Australia, known from Riversleigh fossils. Tooth shape suggests a meat-rich diet; vanished by the late Pleis…

Eland: overview of Africa’s largest antelope Eland Eland are two closely related African antelope species (common and giant). This article covers their appearance, behavior, habitat, diet, reproduction, human interactions and notab…

Elaphrosaurus: a slender Late Jurassic ceratosaurian theropod Elaphrosaurus Elaphrosaurus was a lightly built, long-legged theropod from the Upper Jurassic Tendaguru fauna. Known from a nearly complete postcranial skeleton, its skull is missing and its aff…

Elapids (Elapidae): venomous snakes of cobras, kraits, mambas, and sea snakes Elapid Elapids are a family of primarily tropical venomous snakes with fixed hollow front fangs. This article summarizes their anatomy, diversity, habitats, notable genera, and importance…

Elasmobranchii: sharks, rays and skates — biology, roles and conservation Elasmobranchii Elasmobranchii are cartilaginous fishes including sharks, rays and skates. This article summarizes their anatomy, life history, ecological roles, human uses and conservation challe…

Elasmosaurus: the long‑necked plesiosaur of the Cretaceous Elasmosaurus Elasmosaurus was a distinctive long‑necked plesiosaur from the Late Cretaceous Western Interior Seaway. This article covers its anatomy, discovery, ecology, locomotion hypotheses a…

Elasmotherium — a giant Pleistocene rhinoceros Elasmotherium Extinct genus of large grazing rhinos that roamed the Eurasian steppes from the Late Pliocene into the Late Pleistocene, recognized for a massive skull and likely single front horn…

Electric eel (Electrophorus): biology, behavior, and ecology Electric eel A South American knifefish known for powerful electric discharges used for hunting, defense and electrolocation; an obligate air-breathing predator of the Amazon–Orinoco region.

Electric fish: biology, function, evolution, and human relevance Electric fish Electric fish generate or detect electric fields. This article explains their organs and senses, differences between weakly and strongly electric species, evolution, examples, and…

Electric rays (order Torpediniformes) Electric ray A concise overview of electric rays: anatomy, electric organs, behavior, distribution, taxonomy, and interactions with people and ecosystems.

Elephant: biology, behavior, and conservation of the largest land mammal Elephant Comprehensive overview of elephants: anatomy, social behavior, reproduction, ecological role, threats, and differences between African and Asian species.

Elephant bird (Aepyornithidae) — giant flightless birds of Madagascar Elephant bird Extinct family of enormous flightless birds from Madagascar, known for the largest eggs and close evolutionary ties to kiwis; vanished during the Holocene after human arrival.

Elephant seal (genus Mirounga) Elephant seal Large pinniped of the genus Mirounga with two species in opposite hemispheres; noted for males' inflatable proboscis, deep-diving behavior, strong sexual dimorphism, and a dramatic…

Elephant shrew (sengi): small African mammals of the order Macroscelidea Elephant shrew Elephant shrews, or sengis, are small African mammals with long flexible snouts, long hind legs, and diverse habits. They belong to the order Macroscelidea and are part of the Afro…

Eleutherodactylidae — New World direct-developing frogs Eleutherodactylidae A Neotropical frog family whose members develop directly from eggs into small frogs. Includes the large genus Eleutherodactylus and many island endemics; noted for ecological impor…

Eleutherodactylus: biology and significance of a New World frog genus Eleutherodactylus Eleutherodactylus is a diverse New World genus of small, mainly terrestrial frogs known for direct development, distinctive calls and many Caribbean species such as the coquí.

Eliomys — genus of dormice (garden dormice and relatives) Eliomys Eliomys is a genus of dormice in the family Gliridae. These small, mostly nocturnal rodents occur in Europe, North Africa and western Asia and are known for their bushy tails and a…

Emberizidae: the buntings and New World sparrows Emberizidae Emberizidae is a diverse family of small seed-eating passerine birds including Old World buntings and New World sparrows, with complex taxonomy and a mainly American origin.

Emerald ash borer (Agrilus planipennis): invasive beetle threatening ash trees Emerald ash borer The emerald ash borer is a metallic green beetle native to Asia that has become an invasive pest in North America, killing millions of ash trees and triggering wide-ranging ecologi…

Emperor newt (Tylototriton shanjing) — description, ecology, and care Emperor newt A concise overview of the emperor newt (Tylototriton shanjing): appearance, habitat, behavior, toxicity, and conservation considerations for this brightly marked Southeast Asian sa…

Emperor penguin (Aptenodytes forsteri) Emperor penguin Largest of the living penguins, the Emperor penguin is an Antarctic specialist noted for deep diving, winter breeding on sea ice, and unique incubation on the feet beneath a brood…

Emu (Dromaius novaehollandiae) Emu Large flightless bird native to mainland Australia; second-tallest bird after the ostrich, known for long legs, nomadic habits, male incubation of eggs, and cultural and economic s…

Enantiornithes — Mesozoic "opposite birds" Enantiornithes Extinct clade of Mesozoic avialans known for toothed beaks and clawed wings; diverse Cretaceous birds that left no living descendants and are known mainly from fossil deposits worl…

Endopterygota (Holometabola) — insects with complete metamorphosis Endopterygota Endopterygota (Holometabola) are insects that undergo complete metamorphosis with distinct larval, pupal and adult stages; they include beetles, flies, bees and butterflies.

English Cocker Spaniel A compact, energetic gundog breed from England known for its cheerful temperament, versatile hunting abilities, and distinctive silky coat; popular as both a working dog and a fami…

English Springer Spaniel — breed overview, appearance, history and care English Springer Spaniel Medium-sized, energetic gundog valued for flushing and retrieving. Covers appearance, temperament, history, health, grooming, training and working roles, with guidance for owners a…

Enneabatrachus hechti — a tiny Late Jurassic frog species Enneabatrachus hechti Enneabatrachus hechti is an extinct species of small prehistoric frog known from Late Jurassic fossil remains. Its fragmentary bones contribute to knowledge of early frog evolution…

Ensatina: the lungless salamander complex of western North America Ensatina Ensatina is a group of lungless salamanders (Ensatina eschscholtzii complex) native to moist forests and woodlands from British Columbia to Baja California, notable for variable fo…

Entelodonts — extinct pig-like artiodactyls Entelodont Extinct family of large, pig-like artiodactyls that lived from the middle Eocene to the early Miocene across North America, Europe and Asia; known for massive skulls and omnivorous…

Eoabelisaurus — early abelisaurid theropod from the Middle Jurassic Eoabelisaurus Eoabelisaurus, a Middle Jurassic theropod from South America, is an early member of Abelisauridae known from relatively complete remains; it illuminates the early evolution of shor…

Eohippus — the early Eocene 'dawn horse' Eohippus Eohippus (E. angustidens) was a small, early Eocene equid from North America. Often called the 'dawn horse', it illustrates early stages in horse evolution: small size, multiple to…