Dictionary > Atavism

Atavism

Definition
noun, plural: atavisms
(1) A reversion, or an individual reverting, to an earlier type; an evolutionary throwback.
(2) A reappearance of an ancestral characteristic in an organism after several generations of absence.
Supplement
Atavisms occur due to chance recombination of genes. Genes coding for such traits are preserved in DNA although the genes may not be expressed in some organisms.
Word origin: Latin atavus, a great-grandfather’s grandfather and, thus, more generally, an ancestor.

Related forms: atavist (noun), atavistic (adjective).
See also: pangenesis.


You will also like...

An artistic depiction of a human embryo
Growth and Development of a Human Baby

Upon fertilization, a zygote forms and develops into an embryo. This tutorial elaborates on the growth and development f..

river
Running Water Freshwater Communities

This tutorial introduces flowing water communities, which bring new and dithering factors into the equation for possible..

Neurology of Illusions
Neurology of Illusions

Illusions are the perceptions and sensory data obtained from situations in which human error prevents us from seeing the..

Direct and indirect physiologic effects of growth hormone
Animal Growth Hormones

Hormones are produced in the endocrine glands of animals. The pituitary gland and hypothalamus are the most impor..

Biological Energy
ATP & ADP – Biological Energy

ATP is the energy source that is typically used by an organism in its daily activities. The name is based on its structu..

squirrel
Animal Water Regulation

Animals adapt to their environment in aspects of anatomy, physiology, and behavior. This tutorial will help you understa..