Collard, I am your father.. and mother

Our beautiful Collard

The Collard and its surrounding friends have grown from a seed to full grown, diverse organisms. Since all of these plants are descended from the brassica oleracea, I have to ask: How are there so many different species of the same organism?

Just from looking at our Collard, I can tell that its parents probably looked somewhat like their offspring. Even so, the creation of the cell that started it all (the zygote) is random; there is no way to know definitively from whom our collard got its genes and how the genes were mixed and combined in the mother and father's gametes. 

If our collard makes offspring, we can assume that it will look somewhat like our collard, mixed with the other organism. However, which traits it inherits is actually very random. When a gamete is made, there are two ways the chromosomes can be made unique. The first is crossing over. This is where two chromosomes trade an end of each other's chromosomes:

crossing over

The other way is called independent assortment, where, when the genes are being copied, instead of copying the chromosome gene for gene, the chromosomes are mixed so that the paternal (from the father) and maternal (from the mother) genes are not distinguishable:

However, if we wanted the baby collard to have a certain trait, then we could find the likeliness of it by using punnett squares:

Some are really simple ^

Others.. not so much.

Our collard started as a seed, but how was that seed made? Well, our collard's parents made it by the combining of their two gametes. What are gametes? They are cells which are made by meiosis, a process in which a cell devoted to reproduction splits into 4 unique daughter cells made to combine with a gamete of the other gender to make a zygote, or in our case, a seed. In plant terms, the stamen (or paternal plant structure) combines with a pistil (or female paternal plant structure), which, incidentally, are both contained in each plant.

In return, our collard will pass its traits on to its offspring. However, it is not guaranteed that all of its (or its grandparents') traits will show; it might pass on its recessive alleles, so the phenotype probably won't show our collard's trait, but rather the other brassica oleracea's. It also might pass on some dominant alleles, in which case the phenotype will be like our collard.

A wild collard

Collard comes in many different species, but if you trace back to the ancestors of these species, you would come back to the same plant. This is because evolution has morphed these species into the best possible, so that they have the best possible chance of surviving and passing on their traits.