Jean-Baptiste Lamarck is most recognized today as the French scientist
who proposed that “As organisms adapted to their surroundings, nature also
drove them inexorably upward from simple forms to increasingly complex ones” (O’Neil).
He suggested the strong relationship between environments and species stemmed
from external environmental changes, which affects the animal’s pattern causing
it to accommodate to its surroundings (Jurmain 30). One of his examples was the
explanation of the neck lengths of giraffes. He believed that they evolved as generations
of giraffes reached for higher leaves (O’Neil).
Lamarck’s suggestion goes in line with, “If the environment
changes, the traits that are helpful or adaptive to that environment will be
different”. In his explanation of the evolution of the giraffe, the environment
change are represented by taller trees with higher leaves. The traits of
generations of giraffes are in conjunction with longer necks that help these animal
reach the higher leaves. It is a great example of adaptation to a changing
environment.
As Charles Darwin began his college education at Edinburgh University,
he became aware of Lamarck’s evolutionary theories (Jurmain 34). It is possible
that Darwin could not have developed his theory of natural selection without
the works of Lamarck. Darwin’s natural selection theory has a foundation in
Lamarck’s environment and species adaptations. Furthermore, Darwin’s observation
of the variations of finches found at Galapagos island is a near reflection of
Lamarck’s explanation of the giraffe evolutionary changes. Both animals over
generations have gone through evolutionary changes in order to adapt to their changing
environment; the finches with different sized beaks and the giraffes with different
sized necks. In turn, natural selection gives favor to the animal that is able
to physically adapt to the changing environment in order to survive.
Charles Darwin was hesitant to publish his theory because
he knew it would be highly controversial facing opposition from the church. Evolutionary
theories were viewed as very serious threats (Jurmain 38). Soon enough – after
seeing that he had competition from Alfred Russel Wallace – Darwin published Origins of Species on December 1959.
Okay on your opening discussion, but I don't see how this description differs from Darwin's mechanism of natural selection. Are the two mechanisms the same? How do they differ? What did Lamarck get wrong that Darwin was able to get right? What was Lamarck's mechanism called?
ReplyDeleteI agree that Lamarck recognized the importance of the environment on natural evolutionary processes, but there are more points here you can attribute to Lamarck, including the importance of inheritance and reproduction to evolution. Additionally, I would also have included the point that "individuals don't evolve. Populations do", not because this was Lamarck's point but because he argued the opposite. Darwin recognized the problem with Lamarck's logic and countered it, so this could be viewed as a negative, oppositional influence by Lamarck.
I suggest that you are giving Lamarck too much credit over Darwin's work. Lamarck should certainly be credited as the first to propose an actual mechanism for evolution. This was a huge step forward, regardless of its inaccuracies, but there were many others discussing and debating evolution during Darwin's time, not to mention by the time Darwin was in school, Lamarck's theory was old news and falsified. Lamarck was important but not necessarily indispensable.
For your last section, you are correct, but this is more complex and required more explanation. He delayed publishing for more than 20 years so it is worthwhile to try to understand the reason for this extensive delay. What were Darwin's concerns? And was he only worried about himself or was he also worried about how his family might be impacted by publishing? Remember that his wife was very devout. How might she have been impacted if the church responded negatively to Darwin? Remember that scientists don't work in a vacuum. They can be influenced not just by academics but also by social, cultural and personal issues.