A Matter Of Selection

1. The anatomical trait that has the most variation, in my opinion, would be the shape of the plants’ leaves.  3 groups of plants has smooth-edged leaves, 2 groups had wavy edges, and 1 group had frilly leaves with small limb-like pieces sticking out from the main part of the leaf.  The most ranged trait of the plants was the height of the plants’ stems.  The highest plant’s stem was 4 feet 1 inch, whereas the smallest one was only 10 inches.

Type of leaf	smooth edge	wavy edge	frilly limbs
# of plant groups w/this	3	2	2

2. The reason for the extreme variety in the plants’ traits is due to a long-period change in the gene pool of the species.  Even though all the plants shared a common ancestor, some, due to artificial selection, were mated and whose offspring had inherited traits that were recessive, but were present in both parents.  Also, in some cases, new phenotypes may have entered the population due to mutations.  Natural variation may also have caused so many split-off phenotypes.  Plants with many offspring would have some offspring that had unlikely, recessive genes that resulted in radical (yet useful) phenotypes.  If these offspring mated with similar plants to produce more offspring that had the same outlandish phenotype, then descent with modification predicts that over generations a subspecies would evolve.

3. I believed the most consistent quality of the plants to be the length of their leaves.  While all the plants didn’t have exactly the same length, the similarity is why I thought is to be the least varied trait.  The averages of five species’ plants is shown below.  While a difference of 7 inches (15 being highest and 8 being lowest) may seem large, this is a difference of only about half a foot, not nearly as large as the difference in heights, stated above.

4. For plant breeders to cause this consistency to become non-consistent and create variation, they would have to breed two organisms with the outlier numbers.  If a small-leaved pixie cabbage and a small-leaved kohlrabi were to create offspring, it would be a very likely chance that their offspring would have small leaves.  If these offspring were to mate with other plants that had small leaves, it would be likely that they would produce small-leaved plants.  If breeders were attentive and made sure to mate only the smallest-leaved plants, a new subspecies of plants with tiny leaves would emerge.