Evolution

Can anyone identify the species of flower in the picture below without cheating? It will be revealed at the end of this post.

The flower pictured below is the natural form of a type of flower that humans have selectively bred for their different colors, showy petals and long stems. The modified version we know is a far cry from its naturally occurring form.

Successful reproduction in plants rel

ies on pollination. Plants either use wind or animals to move pollen from one flower to another. Wind pollinated flowers are usually small and incomplete; however animal pollinated plants usually have showy floral parts to attract specific pollinators. Plants have developed adaptations to accommodate desirable pollinators and exclude undesirable pollinators. In selective breeding of roses, humans decide which phenotypes are most desirable and pollinate the plants based on aesthetics.

There are four processes involved in evolution: mutation, migration, natural selection and genetic drift. Although humans are involved in selective breeding, it can cause evolution, as there are changes in allele frequencies in a population, over time.

Aside from dogs, can you think of other wild species that have been selectively bred for our enjoyment (or consumption)?

The answer to the question above is Rosa virginiana, or the Virginia Rose. This is the most common wild rose in the eastern United States. Notice that this rose type has large thorns, large leaves and short stems. It also has fewer petals and the reproductive parts of the plant are larger than it's selectively bred cousins.

http://evolution.berkeley.edu/evosite/evo101/IIIBMechanismsofchange.shtml

http://julietsadler2.articlealley.com/a-little-history-of-roses-803110.html

http://plants.usda.gov/java/profile?symbol=ROVI2

Photo of Rosa virginiana (common name: Virginia Rose)
Provided by: http://emilydecampherbarium.rutgers.edu/pages/Virginia_Rose_jpg.htm