Epigeal
Encyclopedia
Epigeal, epigean, epigeic and epigeous are biological terms describing an organism
Organism
In biology, an organism is any contiguous living system . In at least some form, all organisms are capable of response to stimuli, reproduction, growth and development, and maintenance of homoeostasis as a stable whole.An organism may either be unicellular or, as in the case of humans, comprise...

's activity above the soil
Soil
Soil is a natural body consisting of layers of mineral constituents of variable thicknesses, which differ from the parent materials in their morphological, physical, chemical, and mineralogical characteristics...

 surface.

In botany
Botany
Botany, plant science, or plant biology is a branch of biology that involves the scientific study of plant life. Traditionally, botany also included the study of fungi, algae and viruses...

, a seed
Seed
A seed is a small embryonic plant enclosed in a covering called the seed coat, usually with some stored food. It is the product of the ripened ovule of gymnosperm and angiosperm plants which occurs after fertilization and some growth within the mother plant...

 is described as epigeal when the cotyledon
Cotyledon
A cotyledon , is a significant part of the embryo within the seed of a plant. Upon germination, the cotyledon may become the embryonic first leaves of a seedling. The number of cotyledons present is one characteristic used by botanists to classify the flowering plants...

s of the germinating seed expand, throw off the seed shell and become photosynthetic
Photosynthesis
Photosynthesis is a chemical process that converts carbon dioxide into organic compounds, especially sugars, using the energy from sunlight. Photosynthesis occurs in plants, algae, and many species of bacteria, but not in archaea. Photosynthetic organisms are called photoautotrophs, since they can...

 above the ground. The opposite kind, where the cotyledons remain non-photosynthetic, inside the seed shell, and below ground, is hypogeal
Hypogeal
Hypogeal means "underground".* In botany, a seed is described as hypogeal when the cotyledons of the germinating seed remain non-photosynthetic, inside the seed shell, and below ground...

.

An organism is epigean, epigeic or epigeous if it crawls (epigean), creeps like a vine
Vine
A vine in the narrowest sense is the grapevine , but more generally it can refer to any plant with a growth habit of trailing or scandent, that is to say climbing, stems or runners...

 (epigeal), or grows (epigeous) on the soil surface, or more generally in animal
Animal
Animals are a major group of multicellular, eukaryotic organisms of the kingdom Animalia or Metazoa. Their body plan eventually becomes fixed as they develop, although some undergo a process of metamorphosis later on in their life. Most animals are motile, meaning they can move spontaneously and...

s, neither burrows nor swims nor flies. Consequently, the opposite term depends on the circumstances. It can be fossorial
Fossorial
A fossorial organism is one that is adapted to digging and life underground such as the badger, the naked mole rat, and the mole salamanders Ambystomatidae...

 (burrow
Burrow
A burrow is a hole or tunnel dug into the ground by an animal to create a space suitable for habitation, temporary refuge, or as a byproduct of locomotion. Burrows provide a form of shelter against predation and exposure to the elements, so the burrowing way of life is quite popular among the...

ing), troglobitic
Troglobite
Troglobites are small cave-dwelling animals that have adapted to their dark surroundings. Troglobite species include spiders, insects, fish and others. They live permanently underground and cannot survive outside the cave environment. Troglobite adaptations and characteristics include a heightened...

 - or stygobitic
Stygofauna
Stygofauna are any fauna that live within groundwater systems, such as caves and aquifers, or more specifically small, aquatic groundwater invertebrates, though terrestrial air-breathing subterranean animals are also sometimes included...

, hypogean etc. - (for cave
Cave
A cave or cavern is a natural underground space large enough for a human to enter. The term applies to natural cavities some part of which is in total darkness. The word cave also includes smaller spaces like rock shelters, sea caves, and grottos.Speleology is the science of exploration and study...

-living organisms), or hypogeic and hypogeous (for plants and fungi that grow underground).
The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
x
OK