| To study the genealogical relationship among the ecotypes, we apply the theory of coalescence processes in the following way. |
| It was assumed that factors that are under photoperiodic control would show a clinal order among the ecotypes. |
| Of the nine subspecies recognized, two are forest ecotypes, one living in North America and the other in Eurasia. |
| Geographically isolated populations often have evolved into distinct ecotypes that differ in morphological, life history, or behavioral traits. |
| Further, annual and perennial forms can exist as ecotypes of the same species. |
| The differences in the size of adults inversely reflect the differences observed in the movement rates of ecotypes and populations. |
