Glossary
Altricial
A young animal that hatches or is birthed as relatively helpless and requires some period of intensive parental care, e.g. humans
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Antarctic
The region of the Earth to the far-South , typically defined as within the Arctic Circle (latitude: 60° S)
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Arctic
The region of the Earth to the far-North , sometimes defined as within the Arctic Circle (latitude: 66° 33'N) but also defined as the region in the Northern Hemisphere where the average temperature for the warmest month (July) is less than 10 °C (50 °F), roughly equivalent to where boreal forests stop and tundra begins.
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Asexual Reproduction
A type of reproduction where the offspring inherits the full set of genes from their single parent. It is far more efficient than sexual reproduction but can lead to a buildup of genetic mutations and less diverse populations.
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Brackish water
Water which has more dissolved salts than freshwater but less than saltwater, typically between 500 and 30000 ppm. It is often found in estuaries or areas where saltwater from the ocean and freshwater mix.
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Chitin
A polysaccharide somewhat similar to cellulose that is found in the cell walls of fungi, the exoskeletons of insects and crustaceans, and several other groups.
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Cloaca
A cavity at the end of the digestive tract for the release of excretory and sexual products. It is present in bird, reptiles, amphibians, most fish, and monotremes.
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Derived (Systematics)
A trait, species, or clade that is evolved from a more basal group.
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Ectotherm
An organism that mostly relies on environmental heat sources rather than internal physiological ones like and endotherm does.
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Endotherm
An organism that relies on physiological processes to supply body heat, as opposed to environmental sources like and ectotherm.
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Eukaryota
The taxonomic clade containing organisms whose DNA is enclosed in a nuclear envelope. It is typically referred to as a domain. However, modern genetic analyses suggest that Eukaryotes descended from a group of Archaea, complicating the domain system and sparking debate over where there are two or three domains.
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Family
The third most specific taxonomic rank in biology, between genus and order. It is one of the most commonly used groupings, e.g. Corvidae, the jay family (Crows/Ravens, Jays, Magpies), Pinaceae, the pine family, or Canidae, the dog family. For animals, it typically ends in -idae, whereas for plants or fungi in -aceae.
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Fledge
When a young bird grows sufficient feathers to enable flight and becomes a fledgling
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Freshwater
Water having a low concentration of salts and other dissolved solids, typically less than 500 ppm.
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Fruiting Body
The reproductive structure of an organism, typically of a fungi or bacteria. In fungi, itis typically referred to as a sporocarp and is where the spore-producing structures are found.
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Genus
The second most specific taxonomic rank in biology, between family and species. It makes up the first word of any organism's scientific name, e.g. the word Canis in Canis latrans (coyote).
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Heterotroph
An organism that consumes other organisms for its nutrients, as opposed to autotrophs who obtain energy from light or inorganic chemical reactions.
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Homeotherm
An organism that maintains its body temperature at a constant temperature, even when confronted with hgiher or lower temperature, as opposed to a poikilotherm. They are typically thought of as being endothermic, but some ectotherms are able to maintain a very consistent body temperature.
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Hypha
A cellular structure shared by several unrelated organisms: fungi, oomycetes, and some bacteria. It consists of long, branched filaments of connected cells. In fungi, the cells are typically divided by cell walls called septa and connected by pores in these walls. The hyphae make up the mycelium of a fungus.
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IUCN
The International Union for Conservation of Nature. One of the most influential conservation organisations, having driven many conservation programs to fruition, particularly through the UN. They are most well known for their Red List of Threatened Species and Red List of Ecosystems, which designate species/other taxa and ecosystems which are in the greatest need of protection.
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IUCN Categories
Nine categories that are assigned to species or other taxa by the IUCN (International Union for Conservation of Nature). In order from worst to best: Extinct, Extinct in the Wild, Critically Endangered, Endangered, Vulnerable, Near Threatened, and Least Concern. The remaining two categories are Data Deficient and Not Evaluated. These rankings are often used by international, national, and local governments to make conservation decisions that may impact certain species.
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Kingdom
The second-largest or largest taxonomic grouping of organisms, depending on whether or not you include Domains. It is a higher classification than Phylum. Kingdoms include major categories that most people know: Animalia, Plantae, and Fungi. However, the remaining kingdoms have been continuously reordered over the last several decades as genetic analyses improve. Traditionally, the remaining kingdoms have been Protista, Archaea, and Eubacteria, but these do not appear to be proper groupings, with new research suggesting Protista must be divided into 4 different kingdoms, animals and fungi grouped together as one kingdom, Plantae expanded to Archaeplastida to include red and green algae, and Archaea combined with Eukaryota to form a single Domain.
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Microbe / Microorganism
An organism whose presence is microscopic. They can be single-celled or multi-cellular and exist in every kingdom of life and are by far more plentiful than macroscopic organisms. Microscopic and macroscopic organisms are thought to be about equal in their respective biomasses.
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Monophyletic
A taxonomic group that contains a common ancestor and all of its descendants. This is the correct way to form a clade, as opposed to a paraphyletic or polyphyletic group.
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Monogamous
Having only one mate at a time. This can be further distinguished into two main groups. Social monogamy, where a pair have a living arrangement together, e.g. share a territory, home, raising offspring. Organisms that are socially monogamous may not be sexually monogamous and may consist of extra-pair copulations by one or both partner. Sexual monogamy refers to an exclusive sexual relationship. These two categories can each be subdivided further into serial monogamy, where pairs may change with the breeding season or other factors, and classical monogamy, which is life-long.
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Mycelium
The vegetative part of a fungus, as opposed to its fruiting body. They act as the "roots" of a fungus by absorbing nutrients and water, but also are how a fungus grows and finds other fungi with which to mate.
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Mycorrhiza
A mutualistic relationship between a fungus and a plant. The fungus lives on or in plant roots (although they can be also found in association with rootless plants) and assists the plant with the uptake of mineral nutrients and water, while it receives products of photosynthesis from the plant.
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Near Threatened
A category for extinction risk assigned to a taxon by the IUCN (International Union for the Conservation of Nature). It is the second designation on a scale from extinct to least concern, sitting in between vulnerable and least concern. It indicates that a taxon may be considered threatened with extinction in the near future.
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Order
The fourth most specific taxonomic rank in biology, between Class and Family. It typically ends in -ales
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Paraphyletic
A taxonomic group that consists of a common ancestor and some of its descendants - rather than all of its descendants like a monophyletic group. This makes it a cladistically incorrect group. A commonly seen form of paraphyly is the group Reptilia, which sometimes excludes class Aves, making it paraphyletic since birds are descended from a group of reptiles.
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Parasexual Reproduction
A form of pseudosexual reproduction where genes of different individuals are combined but there is no meiosis or zygote formation.
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Parasitism
A type of symbiotic relationship where one member benefits and the other is harmed. The parasite typically lives in or on the host organism which is its prey. The parasite reduces the fitness of the host, but typically does not kill it (since that would remove their food supply). Those that do eventually kill their hosts are called parasitoids, typically wasps.
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Poikilotherm
An organism whose body temperature fluctuates with the environment or their physical activity.
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Polyandry
A mating system where one female lives and/or mates with multiple males.
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Polygyny
A mating system where one male lives and/or mates with multiple females.
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Polyphyletic
A taxonomic group that consists of multiple groups that are not closely related to each other. This typically occurs due to convergent evolution, where taxonomists noticed a common trait between groups and grouped them together, not realizing that this similarity occurred due to independent evolutionary events.
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Saltwater
Water with a high enough concentration of salts to be higher than freshwater or brackish water, typically above 30 grams per liter or thirty thousand ppm.
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Saprobe
An organism that obtains its nutrients from dead or decaying organic matter.
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Sexual Maturity
The age or circumstances at which an organism is capable of reproduction.
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Sexual Reproduction
A form of reproduction that involves the combination of gametes (such as sperm and egg cells). It leads to far more diverse populations than asexual reproduction but is far less time and energy efficient.
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Sister Taxon
A group of taxa derived from a common ancestor. They are often named as sub-categories, such as sub-family or superfamily.
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Sub-tropical
The region of Earth in between tropical and temperate regions. This region generally has a hot summer and mild winter.
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Symbiosis
An interaction between two organisms living in close proximity. It is often used to refer to a relationship that is beneficial to both organisms, a mutualism, but can also refer to commensalism, parasitism, or amensalism
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Taxon
Any rank of taxonomic group, from Domain to species.
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Taxonomy
An overarching branch of biology concerned with how different organisms are related to one another. The widely used rank system (which now consists of, from largest to smallest, Domain, Kingdom, Phylum/Division, Class, Order, Family, Genus, Species) originated with Carl Linnaeus in the 18th century.
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Tropical
The region of Earth around the center of the globe, typically denoted by being between the Tropic of Cancer (23°26'11.6" N) and the Tropic of Capricorn (23°26'11.6" S). Astronomically, this is the region of Earth where the sun is angled directly overhead a point on the Earth at least once per year. Everywhere else on the globe, the rays of sunlight are always angled. The word can also refer to the climate that is generally posessed by this region, generally hot and wet.
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Zoospore
A type of asexual spore produced by bacteria, fungi, and some other eukaryotes that uses a flagellum for locomotion.