Muroidea (muroid rodents): diversity, classification and significance Muroidea Muroidea is a major superfamily of rodents—mice, rats, hamsters, gerbils and relatives—widely distributed, taxonomically diverse, ecologically important and prominent in research a…
Musk deer (genus Moschus) Musk deer Small, antler-less ungulates of family Moschidae, known for long canines and a musk gland prized by humans; native to Asian mountain forests and subject to conservation concerns.
Musk ox (Ovibos moschatus): Arctic ruminant, adaptations and history Musk ox An overview of the musk ox, an Arctic bovine-like ruminant: appearance, behaviour, range, diet, fossil history, conservation, and human uses such as qiviut wool.
Muskellunge (Esox masquinongy) — North American freshwater predator Muskellunge The muskellunge, or muskie, is a large freshwater predator of the pike family native to northern and eastern North America. Known for its size, ambush hunting and importance to ang…
Muskrat (Ondatra zibethicus) — semiaquatic rodent Muskrat A medium-sized, semiaquatic rodent native to North America, the muskrat builds lodges or burrows in wetlands, shapes plant communities, was important to the fur trade, and has beco…
Musky rat‑kangaroo (Hypsiprymnodon moschatus) Musky rat-kangaroo A small rainforest marsupial from northeast Queensland. The musky rat‑kangaroo is a primitive macropodiform noted for its musky scent, five‑toed hind feet, omnivorous diet and unus…
Mussaurus — an early sauropodomorph from the Late Triassic Mussaurus Mussaurus is a small-to-medium early sauropodomorph dinosaur from Late Triassic Argentina. Known from hatchlings and adults, it illuminates growth, behavior and the early evolution…
Mussel: overview, biology, uses, and ecological importance Mussel Mussels are bivalve molluscs found in freshwater and marine habitats worldwide; they are filter feeders, important ecologically and economically, with notable differences between f…
Mustelid (Mustelidae): diversity, biology, and interactions with people Mustelid Mustelids are a widespread family of carnivorous mammals including weasels, otters, badgers and ferrets. This article summarizes their traits, diversity, ecology, human uses and no…
Mustelinae: overview of a mustelid subfamily Mustelinae Mustelinae is a traditional grouping of small to medium mustelids (weasels, ferrets, minks, martens, wolverines and others). Modern genetics shows it is not a single natural clade…
Mute swan (Cygnus olor): description, range, behavior, and human interactions Mute swan Large white waterbird native to Eurasia, known for its orange bill and graceful posture; widely introduced and culturally significant, with distinctive behavior, distribution, and…
Muttaburrasaurus: an Early Cretaceous ornithopod from Australia Muttaburrasaurus Muttaburrasaurus was a herbivorous ornithopod from the Early Cretaceous of Australia, notable for its distinctive rounded snout and nasal bulge; important for studies of Gondwanan…
My Gym Partner's a Monkey — Animated series about a human student in an animal school My Gym Partner's A Monkey Animated series about Adam Lyon, a human accidentally enrolled at an all-animal middle school, following his friendships, oddball faculty, and comedic attempts to fit in.
Myliobatiformes: the order of rays including stingrays and eagle rays Myliobatiformes An overview of Myliobatiformes — an order of cartilaginous rays (relatives of sharks) that includes stingrays, eagle rays, mantas, and river stingrays; morphology, diversity, ecolo…
Myobatrachidae — the ground and water frogs of Australia and New Guinea Myobatrachidae A family of primarily terrestrial and aquatic frogs native to Australia and New Guinea, with about 100 species in three subfamilies, notable for diverse reproductive modes includin…
Myomimus: the mouse-tailed dormice genus Myomimus Overview of the rodent genus Myomimus (Gliridae), its distinguishing traits, listed species, distribution, ecology, and conservation considerations.
Myomorpha: the mouse‑like rodents Myomorpha Myomorpha is the rodent suborder that contains mice, rats, gerbils, hamsters, lemmings and voles — a diverse, globally widespread group defined chiefly by jaw and tooth anatomy.
Myriapoda: millipedes, centipedes and their relatives Myriapoda A subphylum of terrestrial arthropods with elongated, multi‑segmented bodies and numerous legs. Includes millipedes, centipedes, pauropods and symphylans; important decomposers, pr…
Mysticeti (Baleen Whales) Mysticeti Mysticeti, or baleen whales, are the filter‑feeding suborder of Cetacea distinguished by baleen plates, large body size, and ecological roles in marine food webs; classification in…
Myxophaga: the small suborder of algae‑feeding beetles Myxophaga Myxophaga is a tiny suborder of beetles with about 65 described species in four families. Members are minute, aquatic or semi‑aquatic, and specialized for grazing on algal films in…
Myxozoa: highly reduced parasitic cnidarians of aquatic animals Myxozoa Myxozoa are microscopic, obligate parasites of aquatic animals. Once classified as protozoa, molecular evidence places them within Cnidaria; many have two-host life cycles and sign…
Nabarlek (Petrogale concinna) Nabarlek The nabarlek, or pygmy rock-wallaby, is a small rock-wallaby native to northern Australia, adapted to life among rocky outcrops. This article covers its appearance, ecology, behavi…
Nagtglas's African dormouse (Graphiurus nagtglasii) Nagtglas's African dormouse Small arboreal rodent of West and Central African moist forests; nocturnal, with a bushy tail, insectivorous/omnivorous habits, and a distribution spanning several countries where…
Naked mole-rat (Heterocephalus glaber) Naked mole rat A small, nearly hairless burrowing rodent from East Africa known for eusocial colonies, unusual physiology (reduced pain sensitivity, low metabolism), long lifespan, and interest t…
Namtap (Graphiurus ocularis): the spectacled dormouse of South Africa Namtap Overview of the namtap (Graphiurus ocularis), a small nocturnal dormouse endemic to western South Africa: appearance, habitat, behavior, diet, reproduction, identification and cons…
Nanosaurus — a small bipedal ornithopod Nanosaurus Nanosaurus was a small, fast-moving ornithopod dinosaur from the Late Jurassic of western North America, known from fragmentary remains and noted for a beak, self-sharpening cheek…
Nanotyrannus A small, controversial tyrannosaurid known from a few Late Cretaceous specimens; debated as a distinct genus or juvenile Tyrannosaurus rex, with implications for dinosaur growth an…
Nanuqsaurus — small Arctic tyrannosaurid from Late Cretaceous Alaska Nanuqsaurus Nanuqsaurus is a small tyrannosaurid from Alaska’s Late Cretaceous, known from partial cranial material (DMNH 21461). It is notable for its reduced size and adaptation to high‑lati…
Narwhal — the Arctic 'unicorn' whale Narwhal An Arctic toothed whale (Monodon monoceros) known for the long spiraled tusk, social behavior, seasonal migrations and cultural importance; vulnerable to climate change and human a…
Natterjack toad (Epidalea calamita) Natterjack toad A compact account of the natterjack toad, covering appearance, behaviour, habitat, reproduction and conservation of Epidalea calamita, a distinctive European toad with a yellow dor…
Nauplius (early crustacean larva) Nauplius A nauplius is the earliest free-swimming larval stage found in most crustaceans, with characteristic three pairs of appendages and a single median eye; significant in development,…
Nautilus — the chambered cephalopod with an external shell Nautilus Nautilus are living cephalopods in the family Nautilidae, noted for their chambered external shells, conservative body plan, and long fossil history. They inhabit tropical Indo‑Pac…
Neapolitan Mastiff (Mastino Napoletano) Neapolitan Mastiff A large Italian mastiff breed known for heavy wrinkles, deep protective instincts, and a calm, loyal temperament; used historically and today as a guardian and companion.
Nebulasaurus — sauropod known from a single braincase Nebulasaurus Nebulasaurus is a sauropod genus reported only from a braincase. The limited material offers clues to sauropod neuroanatomy and relationships but requires more fossils to confirm i…
Nectophryne — African tree toads Nectophryne Nectophryne is a small genus of arboreal true toads from West and Central Africa. Two species are recognized; they inhabit moist forests and play ecological roles as insectivores a…
Nectophrynoides — Ovoviviparous toads of Tanzania's Eastern Arc Nectophrynoides Nectophrynoides is a small genus of true toads endemic to Tanzania's Eastern Arc Mountains, notable for internal fertilization and live birth of fully formed toadlets; most species…
Negaprion (lemon sharks): overview of the genus and its species Negaprion Negaprion is a small genus of requiem sharks that includes two large, stocky species known as lemon sharks; this article covers their characteristics, distribution, behavior, and c…
Nematocera: long-horned flies including mosquitoes, midges and crane flies Nematocera Suborder of flies (Diptera) with elongated bodies and multi-segmented antennae. Includes mosquitoes, midges and crane flies. Larvae often aquatic; members are ecologically diverse…
Nematode (roundworm): biology, ecology, and human relevance Nematode Nematodes (roundworms) are a diverse phylum of unsegmented worms found in many habitats. This article covers their anatomy, life cycles, ecological roles, agricultural and medical…
Nemegtosaurus Nemegtosaurus is a Late Cretaceous titanosaurian sauropod known mainly from a skull found in Mongolia's Nemegt Basin. Its classification and relationship with Opisthocoelicaudia re…
Nemertea — ribbon worms (proboscis worms) Nemertea Nemertea (ribbon worms) are mostly marine invertebrates notable for a unique eversible proboscis, diverse life histories, and roles as predators and scavengers across global aquati…
Nēnē (Hawaiian goose) Nēnē The Nēnē, or Hawaiian goose (Branta sandvicensis), is an endemic waterbird of Hawaii noted for its reduced toe webbing, ground‑oriented habits, and conservation recovery from near‑…
Neobatrachia: the diverse, derived frogs and toads Neobatrachia Neobatrachia is the largest suborder of Anura, comprising over 5,000 species of mostly modern frogs and toads with wide ecological, morphological, and reproductive diversity worldw…
Neofelis — the clouded leopards Neofelis Neofelis is a small genus of wild cats comprising the clouded leopard and the Sunda clouded leopard, notable for their cloud-like coat, strong arboreal adaptations, and conservatio…
Neognathae — modern birds: traits, evolution, and diversity Neognathae Neognathae are the major group of modern birds that includes nearly all living species. This article explains their defining features, evolutionary history, major groups, and ecolo…
Neomorphinae — New World ground cuckoos Neomorphinae Subfamily of cuckoos (Cuculidae) native to the Americas. Mostly terrestrial birds including roadrunners and ground-cuckoos, with diverse habits from running predators to some brood…
Neon tetra (Paracheirodon innesi): description, habitat, and aquarium care Neon tetra Small, brightly colored South American freshwater fish prized in aquaria for its iridescent blue and red stripes, schooling behavior, and peaceful temperament.
Neopilina — a modern monoplacophoran genus Neopilina Neopilina is a deep‑sea mollusc genus of monoplacophorans, notable for its rediscovery in the 20th century and its importance to mollusc evolution and paleontology.
