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Informed Discussion of Beekeeping Issues and Bee Biology

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From:
Peter L Borst <[log in to unmask]>
Reply To:
Informed Discussion of Beekeeping Issues and Bee Biology <[log in to unmask]>
Date:
Sat, 30 Nov 2013 08:42:37 -0500
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>Isn't evolution something we observe by looking at how change or adaptation occured? Are we really able to look at something now and note the evolutionary change?

You are right, evolution is about change over time, so it is reasonable to ask what can we see in the present. The conversation started with the question of whether evolution stops when animals are domesticated, since they are no longer subject to natural selection. It was extended to the question of whether human evolution essentially stopped when we began to cook food, or when cities were formed, etc.

Evolution can be described as the effect of natural selection on plants and animals over time. But key to this is variation. Without variation, nothing new would ever come about. We would all be clones of Adam and Eve. Variation is what got the ball rolling in the first place, and is the driving force that resulted in the millions of different species of life, which can be found in locations ranging from the hot springs to the bottom of the ocean.

Not only do organisms vary by so-called random mutations, but mechanisms have evolved to capitalize on the variation such as sex. Sex is an amazing system where plants and animals present their features as "available" so that prospective mates will choose them and thereby acquire traits that they incorporate into their offspring. 

In other words, if a family of warriors wants to produce better warriors, the men may seek other families with great warriors and marry their daughters, in hopes of producing sons with the best characters of both families. In honey bees, the system is slightly different, in that the queen does not only seek the best drones, but also a variety of them. 

This is why we talk so much about variety and diversity in honey bees, since evolution has produced a system to increase diversity and prevent narrowing of the gene pool, which is the very opposite of artificial selection, or line breeding, which tries to single out characters and enhance them, often at the expense of other characters.

But as to what we can observe in the present: the short answer is: the mechanisms that produce evolution over time are present and operating in real time. These mechanisms have never stopped, they certainly haven't been weeded out by excessive selection. In fact, honey bees have been found to have a high rate of recombination which is the shuffling of gene combinations. Also, we have learned that the shuffling is not random but is directed by mechanisms

Have you ever watched a great card player in action, like Ricky Jay? When he shuffles the deck it looks like he is shuffling the cards in the ordinary way, but the results are always amazing. So he is control the cards in such a way that he gets results he wants, whereas when you or I shuffle, we are happy if they are just well mixed and our chances of getting a great hand are at least as good as the guy across the table. If we play our cards right, maybe we can improve the hand.

Evolution is the result of a set of processes. It is also those processes (also products of evolution) and can be studied in real time.

Pete

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