释义 |
polytomy
po·lyt·o·my P5467550 (pə-lĭt′ə-mē)n. In a cladogram, a point from which two or more new branches diverge, representing either of two cases:a. A multiple speciation event in which two or more species diverge from the same ancestor. Also called hard polytomy.b. A speciation event in which two or more species are presumed to descend from the same ancestor, but the order of speciation is unknown. Also called soft polytomy. [poly- + -tomy (on the model of dichotomy).]
polytomy
polytomy (pə-lĭt′ə-mē)n. In a cladogram, a point from which two or more new branches diverge, representing either of two cases:a. A multiple speciation event in which two or more species diverge from the same ancestor. Also called hard polytomy.b. A speciation event in which two or more species are presumed to descend from the same ancestor, but the order of speciation is unknown. Also called soft polytomy. |