Pronunciation: di-KA-to-mi
Etymology: Dichotomy is derived from two Greek roots that mean two (dyo, δύο) and cuts (tomi, τομή).
A dichotomy is a type of branching such that two branches emerge from a single node. Many plants exhibit aspects of dichotomous branching or dichotomous growth (e.g. dichotomous venation, dichotomous branching, dichotomous growth).
The dichotomous key is a deductive construct which Biologists use to determine an unknown taxon through a set of nested dichotomous statements.
In a cladogram, a dichotomy is the emergence of two branches from a node. Below, the cladogram of venomous coelenterates has three dichotomies:
- jellyfish + box jellies
- (dichotomy 1) + hydroids, blue bottles & fire corals
- (dichotomy 2) + stinging anemones & bubble corals
| By Jack R. Holt. Last revised: 01/02/2009 |
