Evolution Before Darwin Flashcards
what is evolution?
is heritable change in a population or species over generational time, and the divergence of lineages from a common source
Evolution involves these three things
it is more than just elimination of inviable forms
change is open ended
species are related by descent
What were Obstacles to evolutionary thinking?
essentialism implies fixed species characteristics
everyday experiences shows us generational continuity, not radical discontinuity
literal interpretation of religious texts, and belief in supernatural causation in this world, can lead to the rejection of all science
What was Natural theology in the 18th and 19th century?
Natural theology was a new term in the 18th and 19th century for the teleological interpretation of organismal function, which goes back to ancient times
Who was the most important figure in England in terms of Natural theology? What did they use as proof of their views?
William Paley, author of Natural Theology 1802. Tried to disprove evolution by using the human eye as an example of something too perfect to be the product of nature.
Another Obstacle to evolution was incomplete fossil records. Who though that fossil records showed abrupt rather than gradual changes in life?
Cuvier in the early 19th century the intermediates that he thought he should see if evolution had occured he didnt see
What is the plenitude principle?
that all species that can exist, do exist. Creation was fully stocked from the beginning; gaps in creation cannot exist
what did many people fear that evolutionary thinking would cause?
would cause moral and societal chaos, because it undercuts the credibility of the bible as an infalible document, and because it implies humans are “mere” animals and might start behaving like them
what was linnaeans contribution to indications of evolutionary change?
Linnaean hierarchies and natural groupings
What differentiates similarity due to function from similarity due to unity of type?
Function: animals share a different structures which accomplish same purpose (ex: bug wings v bird wings)
Unity of type: animals share a similar structure but use it for different purposes (ex: penguin wings v sparrow wings)
fossils contribution to the indications of evolutionary change?
the sequence of fossils in the stratigraphical column and the reality of extinction
what was spontaneous generation of organisms contribution to the indications of evolutionary change?
if small organisms such as bacteria and protozoa can arise by spontaneous generation, and then evolve into more complex forms we need not invoke the creation of an unchanging world.
LOL too bad this was not correct
what was Natural theologies contributions to the indications of evolutionary change?
although natural theology implied a creator and a designer, and therefore worked against the idea of evolution it also focused attention on adaptation and function, which stimulated the growth of evolutionary thinking
inherited variability within species did what for the indications of evolutionary change?
if species were created to be adapted to their environment, why should there be any inherited variability at all? How could there be any variability.
ex recurrent laryngeal nerve of the giraffe
what did the topic of time and environmental changes raise questions about the indications of evolutionary change?
how could well adapted organisms remain well-adapted though long periods of environmental change
how did the idea of change over time penetrate the euopean consciousness?
the solar system formation and evolution
a solar arrow of time- exhaustion of the sun’s energy stores
gradual geological changes over long periods of time
similarities amoung words in sanskrit, latin and greek suggested they were descended from a common language, now extinct
Who was Erasmus Darwin(1731-1802)?
charles darwins grandfather was a scientist, poet and physician
What was Erasmus Darwin’s book called? What was it written about?
Zoonomia (1796), which set forth a thoery of evolution similar to Lamarck’s.
What was Darwins evidence for evolution?
Mammals formed natural groups
Understand why there are natural groups
Functionally interdependent - not true
Mammals descended from common ancestor
Aware of non functional
Parts of the human body
what did Darwin conclude about warm blooded animals?
that they were descended from one common ancestor from “one living filament, which the great first cause endowd with animality”
Who was Lamarck (1744-1829)?
A PHYSICALLY AND INTELLECTUALLY courageous man who was an accomplished botanist until he was 50 then he started working for the Museum of natural history as a zoologist where he made many contributions to invertebrate zoology
What were some of larmarck’s contributions to zoology?
Keys
Natural groups
Biosphere
Invertebrates
Lamarck’s ideas on evolution were put down into three books what were they?
zoological philosophy (1809)
natural history of invertebrates 1815
analytical systems of positive knowledge about man 1820
Why did Lamarck believe that life evolved?
linnaean hierarchies suggest relationships
the reality of environmental change means the evolution must occur if life is to survive
evolution solves the problem of extinction; new species evolved to take the place of vanished ones
