Ever since I was a child, I have always considered the city of Chicago as my home away from home.  Although I was born and raised in Houston, my Aunt lives in the windy city and I have been lucky enough to be able to visit her and my cousins at least a few times every year. After my brother graduated from the University of Texas, he too moved to Chicago resulting in an even further increase in the frequency of my trips there.

As the historical home of the modern day skyscraper, many view this great city simply as a cold urban jungle no different from any other large metropolis. In my opinion, however, this description does an absolute injustice to Chicago. One of my favorite new developments of the city is the beautiful Millennium Park along the gold coast of Lake Michigan. In addition to modern architecture such as the famous chrome “bean”, the Millennium Park is also known for its extensive botanical garden often considered to be one of the most beautiful in the entire World.

Whenever I visit there in the spring and summer, the diverse array of flowers with their exotic and gorgeous colors never ceases to amaze me. Dominating plant life, flowers have vexed evolutionary biologists ever since the days of Charles Darwin. Finally, however, a study led by Dr. Tim Brodribb and Dr. Taylor Field at the University of Tasmania and University of Tennessee has revealed some insight as to how exactly these beautiful plants came to reach this unbounded supremacy of plant life on earth.

Through their research, Dr. Brodribb and Dr. Field were able to deduce that flowering plants were able to dominate plant life by evolving more efficient and extensive hydraulics that tremendously aid the process of photosynthesis. They were able to reconstruct the historical evolution of these flowering plants and discovered that a mutation that improved angiosperms’ hydraulics pushed these species of plants to a much higher photosynthetic capacity and consequently, made them much more evolutionarily fit in comparison to other plants.

Speaking of his study, Brodribb concludes, “Without this hydraulic system we predict leaf photosynthesis would be two-fold lower then present so it is significant to note that without this evolutionary step land plants would not have the physical capacity to drive the high productivity that underpins modern terrestrial biology and human civilization.”

No matter how much my knowledge of biology increases over the years, I am still left dumbfounded as to just how amazing the consequences of natural selection often are. Just imagine how much beauty the world would be lacking from if flowering plants never mutated and consequently did not come to dominate plant life on earth. The next time I get the opportunity to visit Millennium Park in Chicago, I will make sure not take its glorious botanical gardens for granted.

Discussion Question: Given your knowledge of evolution, why do you think angiosperms began to develop the gorgeous colors that often characterize their petals?

News Article: http://www.sciencedaily.com/releases/2009/12/091201100221.htm
Scientific Article: http://www.jstor.org/pss/1514632