Glossary: M

Malpighian tubules

Excretory tubules opening into the midgut which function to remove nitrogenous wastes in the form of uric acid. Synapomorphy of the Myriapoda+Insecta. Convergent in Arachnids.

Mediterranean climate

A climate with cool wet winters and dry summers.

Müllerian mimic

a form of mimicry in which several harmful species have evolved to resemble each other or share similar warning signals, thereby being protected from predation.

macroalgae

seaweed. Algae that are large and photosynthetic.

macroscopic

a size scale very much larger than that of atoms and molecules, macroscopic systems are governed by classical physics.

madreporite

an anatomical feature of echinoderms (Phylum Echinodeermata), a calcareous sieve leading the the water vascular system.

magnetic

(as perception channel keyword). This animal has a special ability to detect the Earth's magnetic fields.

mainland endemic

see endemic. Native to a mainland area.

male parental care

parental care is carried out by males

mallee

A grassy, open woodland habitat characteristic of many semi-arid parts of Australia. Mallee also describes the multi-stemmed habit of eucalypt trees which dominate this habitat.

mammary gland

milk-producing glands found in female mammals, consisting of clusters of milk-producing alveoli and a system of ducts for transporting the milk to an external nipple or teat. These glands typically occur in pairs and begin secreting milk after gestation, plural is mammae.

See Also: lactation
mandible
  1. One of a pair of hardened mouthparts, modified from the third segment, found in insects, crustaceans, millipedes, and centipedes. The mandibles lie in front of the maxillae and their movements help in biting and crushing food. Synapomorphy of the Crustacea+Myriopoda+Insecta.
  2. The lower jaw of vertebrates.
  3. Either of the two parts of a bird's beak.
mangrove forest

A tropical forest that has developed on sheltered, muddy shores of deltas and estuaries exposed to tide. The vegetation is almost entirely woody.

mantle

the fold of skin that covers the dorsal surface of molluscs and extends into lateral flaps that protect the gills in the mantle cavity. the outer surface of the mantle secretes the shell. Synapomorphy of Mollusca. (The body wall of tunicates is also referred to as the mantle.)

manure

typically livestock excrement

marsh

marshes are wetland areas often dominated by grasses and reeds.

marsupial

A member of a group of mammals (Metatheria) 1) that generally do not have a placenta and 2) whose females generally have a pouch on the abdomen containing the nipples, where newborn young are carried. Marsupials include bandicoots, kangaroos, opossums, wombats, possums, koalas, and others.

marsupium

in marsupial mammals, an external pouch or fold in which the mammae occur and in which young continue to develop after birth. Temporary eternal folds, sometimes called marsupia, may form in other groups of animals (fish, crustaceans, amphibians) for the purpose of egg protection or incubation.

See Also: marsupial
mast

large crops of seeds or nuts which accumulate on the forest floor and serve as food for animals.

masticate

chew, or process for eating

matriarchal

Relating to a type of social organization among animals where the family group is lead by a female.

matriline

A related group of animals linked by descent through females alone.

maxilla
  1. One of a pair of mouthparts found in insects, crustaceans, millipedes, and centipedes. They lie behind the mandibles and their movements help in food processing. Crustaceans have two pairs of maxillae (plural) but in insects the second set is fused to form the labium.
  2. One of a pair of large, tooth-bearing bones in the upper jaw of vertebrates. In mammals they carry all of the upper teeth except the incisors.
medicine

a substance used in treating disease.

medusa

the free-swimming stage in the life cycle of cnidarians (synapomorphy of Phylum Cnidaria). Examples are jellyfish.

megasclere

large spicules, found in sponges (Phylum Porifera).

melanin

a dark brown pigment of the skin, eyes, and hair of animals, especially vertebrates, that is produced in epidermal cells called melanophores or melanocytes.

melanistic

Having a high level of dark pigmentation, resulting from high levels of melanin, which produces a very dark or black color in skin, eyes, fur, or scales.

meroblastic

a pattern of egg cleavage in early development in which only the yolk-free portion of the egg divides with each cell division. This pattern is found in animals whose eggs contain high proportions of yolk, examples are birds.

mesic

A habitat characterized by a moderate amount of moisture.

mesoderm

The middle of the three germ layers (Ectoderm, mesoderm and endoderm). It is formed during gastrulation, and gives rise to connective tissues, muscle, urogenital and vascular systems, and the peritoneum. Synapomorphy of the Bilateria.

mesoglea

the layer of jelly-like material between the two tissue layers, gastrodermis and epidermis, of cnidarians (fibrous in Phylum Cnidaria) and ctenophores (Phylum Ctenophora). It is also used sometimes to refer to the jelly-like matrix found between epithelial layers in sponges (Phylum Porifera).

mesohyl

the gelatinous matrix surrounding sponge cells, sometimes also called mesoglea or mesenchyme.

metachronal

an error in chronology when an event is recorded as having occurred after its real time.

metamorphosis

A large change in the shape or structure of an animal that happens as the animal grows. In insects, "incomplete metamorphosis" is when young animals are similar to adults and change gradually into the adult form, and "complete metamorphosis" is when there is a profound change between larval and adult forms. Butterflies have complete metamorphosis, grasshoppers have incomplete metamorphosis.

micropyle

an opening in the surface of a plant ovule through which the pollen tube passes.

microsclere

small spicules, found in sponges (Phylum Porifera).

migratory

makes seasonal movements between breeding and wintering grounds

mimicry

imitates a communication signal or appearance of another kind of organism

molecular genetics

The branch of genetics that deals with issues such as how a gene is copied, how a mutation arises, how genes are turned on and off when their activity is needed or not needed, what are the chemical products of genes, and what is the precise sequence of the chemical building blocks of DNA in genes.

molluscivore

eats mollusks, members of Phylum Mollusca

molt

to shed exterior covering (such as fur, feathers, skin, or exoskeleton). In birds, molting also includes the process of growing replacement feathers. In other species, the new covering is uncovered when the old is lost. In Ecdysozoa (where molting is a synapomorphy) this process of periodically shedding the non-expandible outer cuticle is also called Ecdysis.

monochromatic

having a single color

monogamous

Having one mate at a time.

monomorphism

having the same appearance (for example, in sexual monomorphism the sexes are alike).

monophagous

Referring to an organism that subsists on only one kind of food.

monophyletic

Referring to a group of organisms with a single, common ancestor, and containing all descendants within that group.

monotypic

Referring to a genus that comprises a single species (see Scientific name).

montane

Pertaining to mountainous country.

motile

having the capacity to move from one place to another.

mountains

This terrestrial biome includes summits of high mountains, either without vegetation or covered by low, tundra-like vegetation.

mutualist

this species has a close beneficial relationship with at least one other plant or animal species. It helps the other species live, and the other species helps it.

mycophage

an animal that mainly eats fungus

myocyte

a contractile cell, mainly muscle cells.

myomeres

Muscle segments that comprise the trunk musclature and derivatives of an organism. Synapomorphy of the Craniata+Cephalochordata.