Zoology glossary ~ G

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Gamma Diversity
The inclusive diversity of all the habitat types within an area; regional diversity.

Gaping
"A foraging technique in which a bird thrusts its bill into the soil and forcibly opens the bill, creating an opening."

Gelding
A male horse that has been castrated.

Gene Flow
Exchange of genetic traits between populations by movement of individuals, gametes, or spores.

Gene Frequency
The proportion of a particular allele of a gene in the gene pool of a population.

Gene
Generally, a unit of genetic inheritance. In biochemistry, gene refers to the part of the DNA molecule that encodes a single enzyme or structural protein.

Generalist
A species with broad food or habitat preferences.

Generation Time
Average age at which a female gives birth to her offspring, or the average time for a population to increase by a factor equal to the net reproductive rate.

Genetic Drift
Change in allele frequency due to random variations in fecundity and mortality in a population.

Genetic Feedback
Evolutionary response of a population to the adaptations of competitors, predators, or prey.

Genetic Variance
Variation in a phenotypic value within a population due to the expression of genetic factors.

Genome
The cell's total complement of DNA: in eucaryotes, the nuclear and organelle chromosomes; in procaryotes, the major chromosome, episomes, and plasmids. In viruses and viroids, the total complement of DNA or RNA.

Genotype
All the genetic characteristics that determine the structure and function of an organism; often applied to a single gene locus to distinguish one allele, or combination of alleles, from another.

Gharial
Asia, fish-eating crocodilian with a very narrow snout.

Gizzard
A chamber of an animal's digestive tract specialized for grinding food.

Gonads
The testes or ovaries.

Gorget
"Iridescent throat patch on hummingbirds."

Greenhouse Effect
Warming of the earth's climate owing to the increased concentration of carbon dioxide and certaain other pollutants in the atmosphere.

Gross Production
The total energy or nutrients assimilated by an organism, a population, or an entire community.

Group Selection
Elimination of groups of individuals with a detrimental genetic trait, caused by competition with other groups lacking the trait; often called intergroup selection.

Guano
"Large deposits of bird feces that accumulate in sites that birds regularly use, such as breeding colonies."

Gular Fluttering
"A cooling behavior in which birds rapidly flap membranes in the throat to increase evaporation; particularly obvious in cormorants, pelicans, and their relatives."

Gular Pouch
"A bare throat pouch that can be expanded to accomodate large prey; found in pelicans and their relatives."