A geometric shape formed by two cones joined at their bases, sometimes used to describe structures in biology.

A genetic recombination event in which two crossovers occur between chromatids, leading to the exchange of genetic material between chromosomes.

A genetic cross that tracks the inheritance of two traits, often used to explore the interactions between two genes.

The period it takes for a population of organisms or a cell culture to double in size.

Soft, insulating feathers found beneath the contour feathers of birds, providing warmth.

The process by which two or more related species become more dissimilar over time, often due to adaptation to different environments or ecological niches.

A type of natural selection that favors extreme phenotypes at both ends of the spectrum, increasing genetic diversity within a population.

The process of cell division (mitosis or meiosis) that results in the formation of new cells, or the division of organisms into smaller units or categories.

Twins that develop from two separate fertilized eggs, genetically no more alike than ordinary siblings.

Abbreviation for dextro-levo, often used to denote the optical rotation of a molecule in one direction.