Glossary

70 terms beginning with E · showing 1–40

1. ecological niche

   The specific position or function that an organism fills in an ecosystem.

   Used in 77 profiles

2. ecology

   Study of the interactions occurring between organisms and their environments; also used to refer directly to such relationships.

   Used in 18 profiles

3. ecophenotype

   A phenotype resulting from environmental or ecological conditions rather than genetic inheritance.

4. ecosystem

   A biological community comprising interacting organisms plus their physical environment.

   Used in 23 profiles

5. ecotype

   A distinct population of a species adapted to occupy a particular habitat due to localised natural selection.

6. ectoparasite

   A parasite that lives outside its host. Opposite of endoparasite.

7. ectopterygoid

   A membrane, paired, bone in the upper jaw, located ventrally on the skull. Some fishes, such as serrasalmids, possess small tooth-like projections known as ectopterygoid teeth on this bone.

   Used in 4 profiles

8. eddy

   Movement of water in the opposite direction to the main current, especially in a circular fashion; a whirlpool.

9. edema

   See oedema.

10. egg

    Object laid by a female bird, reptile, fish, or invertebrate, normally roun or oval-shaped and containing a developing embryo surrounded by nutrient material and a protective case or shell; a female gamete; an ovum.

    Used in 1,063 profiles

11. egg scatterer

    A species spawning above the bottom which scatters demersal eggs randomly.

    Used in 81 profiles

12. Elasmobranchii

    Subclass of Chondrichthyes, also known as cartilaginous fishes, that includes the sharks, skates and rays.

    Used in 12 profiles

13. elasmoid scale

    Common scale-type. Found in all teleosts, and often separated into cycloid and ctenoid forms.

14. electrofishing

    Method of collecting fishes that uses electricity to stun them, commonly used for sampling populations during scientific surveys. Causes no permanent harm to fishes when carried out properly.

    Used in 1 profile

15. electrogenesis

    Production of electrical impulses in living organisms or tissues.

16. electrogenic

    Of or relating to production of electricity in living cells, sometimes used to in reference to fishes able to deliver an electric shock.

17. electroreceptor

    Sensory organ present in some fishes. Used to detect electrical current.

    Used in 4 profiles

18. emarginate

    Having a notched margin or edge. Often used in reference to a caudal fin with a slightly concave shape.

    Used in 101 profiles

19. embryo

    A young, unborn or unhatched organism in the process of development.

    Used in 11 profiles

20. empirical

    Derived from or relating to experimental observation as opposed to theory.

    Used in 1 profile

21. Enchytraeus

    Genus of annelid worm of which two species, E. albidus and E. buchholzi, are cultured by aquarists to use as fish food.

22. endangered

    Threatened by extinction.

    Used in 64 profiles

23. endemic

    Belonging or native to a particular area or country.

    Used in 555 profiles

24. endobenthic

    Dwelling within the sediment at the bottom of a water body.

25. endocrine

    Of, relating to, or denoting glands that secrete hormones or other products directly into the blood: 'the endocrine system'.

26. endoparasite

    A parasite that lives inside its host. Opposite of ectoparasite.

27. endorheic

    Used in reference to a closed drainage basins with no outflow to other bodies of water, the bottom of which often contains a salt lake or salt pan. Water leaves only via evaporation or seepage.

    Used in 7 profiles

28. endosymbiont

    A symbiotic organism that lives within the body of its host.

29. endosymbiosis

    Form of symbiosis in which one organism lives inside the other

30. epaxial

    Above, or on the dorsal side of, the axis of the skeleton.

    Used in 1 profile

31. epaxial lobe

    Section of the caudal fin located between the base and dorsal margin.

32. ephemeral

    Short-lived; transitory; existing only briefly.

    Used in 11 profiles

33. epibranchial

    Bone or cartilage forming the upper part of the gill arch, positioned between the ceratobranchial and pharyngobranchial.

    Used in 90 profiles

34. epibranchial organ

    Present in some microphagous fishes and comprises a paired dorsal diverticulum located towards the posterior of the pharynx. In the majority of species it's divided into two sections by additional gill rakers which trap small food particles.

35. epidermis

    The outermost, protective, non-vascular layer of skin in vertebrates.

    Used in 5 profiles

36. epigean

    Dwelling or existing above ground. Opposite of hypogean.

    Used in 1 profile

37. epineural

    Arising from or located on a neural arch of a vertebra.

38. epiphyte

    A plant growing attached to another but not parasitic upon it.

39. epithelium

    Refers to layers of cells that line hollow organs and glands or make up the outer surface of the body. Epithelial cells help to protect or enclose organs and most produce mucus or other secretions. They're arranged in single or multiple layers, depending on the organ and location.

    Used in 24 profiles

40. epural

    Located on the dorsal side of the caudal fin; elongate bone which supports the caudal fin rays, positioned above the urostyle and posterior to the last neural spine.

    Used in 8 profiles