Evolution Flashcards
What is essentialism?
A plato belief that species are fixed within a grand scale of nature (scala naturae)
What is Aristotle thinking ?
This was an early attempt at classification where keen observations were made between animals and plants.
With the Aristotle method what two groups were animals divided up into?
With or without red blood.
Who developed the coherent (binomial) system for describing, classifying and naming organisms?
Carl von Linne (Linnaeus)
What year was the binomial system (Systema Naturae) created?
1735
What is creationism?
Living things and Earth physical structure are permanent.
What is catastrophism?
Geologically only catastrophic events had changed the geological structure of the earth.
How did Cuvier explain changes seen within fossilized bones?
Result of a previous catastrophic event.
What was the first step progressive step towards a more accurate evolutionary theory?
When looking at a sample from the Quarries of the Paris Basin.
1st uppermost layer: Lots of lake and freshwater marsh fossils and plants
What was the first step progressive step towards a more accurate evolutionary theory?
When looking at a sample from the Quarries of the Paris Basin.
1st uppermost layer: Lots of lake and freshwater marsh fossils and plants.
2nd layer: Sandstone with marine fossils.
3rd layer: Gypsum, limestone and marine fossils and a few freshwater forms.
4th layer: Course grained limestone and marine fossils and some freshwater forms.
5th layer: Chalk, clay, sand and freshwater shells and driftwood.
What were Darwin’s key observations on his voyage on HMS Beagle?
The succession of types: Similarity between extinct Glyptodonts and skeletons of living armadillos.
Representative types: Geographical grouping of different types of Rhea.
Evidence from islands: Animals on oceanic islands resembled those on nearest mainland but also varied slightly between islands.
What were Darwin’s reasons for his evolutionary theory?
That the world is continually changing so life must also change to survive.
Nature provides an unlimited supply of unsolicited, fortuitous and hereditary novelties.
The fertility of nature leads to a struggle for existence.
Individuals with favourable novelties survive and reproduce better and leave more descendants.
What were the key points Darwin made in his book Origin of Species?
Species were Immutable (not fixed)
He recognised that artificial selection (breeding dogs) can change the morphology of organisms to suit man. So natural selection can change morphology to suit the environment.
This could eventually lead to a new species.
What are the conditions required for evolution?
More individuals are produced than can survive.
There is heritable variation between individuals.
Some individuals will be better adapted than others.
Best adapted (fittest) individuals will leave behind the most offspring.
What influential people opposed Darwin’s book, Origin of Species and why?
Adam Sedwick, Louis Agassiz, Richard Owen and Bishop Samuel Wilberforce.
Because of their religious views.
What was one of the main 19th century criticisms made by biologist St George Mivart?
How does natural selection explain the evolution of such complex structures like the eye?
In answer to St George Mivart’s critisism, how can you evolve the eye in 2000 steps?
The shape of the eye changes at random by 1%. Because selection retains only those changes that improved the optical performance of the eye. 2000 steps would generate a vertebrate eye.
For realistic values of heritabilty and strength of selection, it would take 400,000 generations to evolve a vertebrate eye. If one generation = one year, how many years would it take to evolve?
Half a million years.
If evolution occurs by accumulation of small changes, why are so many
intermediate types absent from the fossil record?
This is due to a sudden rapid mutation over time in between each stasis.
