Evolution Flashcards
Define evolution.
A theory of how life changes over time
Who was responsible for adopting the theory of evolution?
Charles Darwin
What did James Hutton propose?
Earth has been slowly shaped by geologic processes over very long periods of time
Concluded that the earth must be millions of years old
What did Charles Lyell propose?
Geologic processes that shaped the Earth over long periods in the past are the same processes that operate today
explain Use + disuse
Body parts used extensively to cope with the environment become larger and stronger while those that are not used deteriorate
Example: wings animals did not use its wings, they’d decrease in size and then disappear
explain Inheritance of acquired traits
Modifications that an organism acquires during its lifetime can be passed onto offspring
Example: giraffes elongated neck due to stretching is inherited by its offspring, gradually becoming longer and longer throughout generations
explain Tendency towards perfection
All organisms have an innate tendency toward perfection, hence they continually develop features that help them live more successfully in their environment
Example: birds had the urge to fly, so over many generations they kept trying to fly and their wings increased in size and became more suited for flying
Briefly describe what natural selection is.
Populations change over time because individuals who inherit traits best suited to their environment leave more offspring than less suited individuals, leading to radial, favorable changes in the population
Define gene pool.
A common group of genes is called a gene pool
What does allele frequency mean?
The number of times an allele occurs in a gene pool, as a percentage of the total occurrence of ALL alleles for that gene pool
example of Lateral gene transfer
Single celled organisms is common and is creating diversity and conjugation
example of mutations
Bajau people
examples of genetic recombination
Brother having blonde hair but you having brown hair
define homologous structures
similar physical features in organisms that share a common ancestor, but the features serve completely different functions
define analogous structures
anatomical features that are superficially similar to one another
