Definitions

Nacre The innermost, lustrous layer of a mollusc shell, secreted by the mantle, mother-of-pearl.
Natality births
Natural history the study of nature
Native Indigenous. Living naturally within a given area.
Naturalized an alien, or introduced species, that has become successfully established
Natural selection The differential success in reproduction of different phenotypes resulting from the interaction of organisms with their environment
Nauplius the earliest larval stage of Crustaceans when they (usually) have 3 pairs of functioning limbs
Nautiloid A free-swimming marine animal in the phylum Mollusca. It has a coiled, chambered cell.
Nectar the sugary substance secreted by flowers to attract insects so aiding pollination
Nectarivorous feeding on nectar
Nematocyst the stinging cell of cnidarians
Nematodes Unsegmented round worms, usually small, often parasitical.
Nematomorpha hairworms, Gordian worms, horsehair worms
Nemertea ribbon worms
Neonatal newborn, recently hatched
Neoteny the retention of juvenile features into the adult stage
Nephridium a excretory tube in earthworms
Nest odour the distinctive odour of a nest enabling the inhabitants to distinguish their nest from the others, e. g. as in social hymenoptera
Nest parasitism symbiosis between 2 termite species where one colony lives in and feeds on the walls of the nest of another (host) species
Neurons Nerve cells which receive and transmit stimuli.
Neuroptera the order of insects containing the lacewings, alder flies, ant lions etc.
Neurotoxin A substance that deactivates nerves or that disrupts the way nerves work. Some insects can produce neurotoxins and they are commonly found in many insecticides.
Niche the limits for all important environmental features, within which individuals of a species can survive, grow and reproduce.
Nit an egg of a louse, especially the human head louse
Noctuidae family of moths containing the cutworms and army worms
Nocturnal Active at night
Nomad a wandering organism
Nomenclature the system and application of scientific naming of species
Noosphere that part of the biosphere altered or influenced by man
Notochord A reinforcing rod that runs the length of the body. It is found in chordates.
Notostraca tadpole shrimp
Nucleus The central body in a eukaryotic cell. It contains the genetic information on chromosomes.
Nuda a class of sea gooseberry (Ctenophora)
Nuptial flight the mating flight of insects, especially social insects, where it involves the queen mating with males.
Nutrient cycle the path of a chemical substance (carbon, nitrogen, etc.) back and forth between the living and non-living worlds
Nymph the immature stage of certain insects in which there is some similarity to the adult form