descent with modification part 1 Flashcards
world view
our core belief about how the world works
biological evolution:
population characteristics change over time
microevolution
changes in characteristics (traits) within a population
macroevolution
changes in characteristics are large enough to result in a new species
science can only be used to…
answer questions that are testable (using empirical evidence)
examples of things that cannot be answered by science
aesthetics, morality, existence or absence of God
methodological naturalism
-event I am currently observing has only natural causes
(everyone in science)
metaphysical naturalism
belief that ALL events have only natural causes
-requires faith that science fully explains the nature of reality
what, like faith, is outside of science?
metaphysical naturalism
the debate between christianity and evolution often falls into a…
false dichotomy: limits discussion to only 2 opposing perspectives while ignoring additional perspectives
recent creation
the biblical story of creation is scientifically accurate
what do recent creationists believe about creation?
-God created the world in 6 literal days
-age of life is 6,000-10,000 years old
-earth may have been created with an appearance of age
-fossil record created by the flood
recent creationists view on evolution
only small evolutionary changes in organisms
progressive creation
our belief of origins must NOT ignore the evidence in nature
progressive creationists view of creation:
-each day of creation indicates a long day or days were spread apart
-age of life is old
according to _____, living organisms are created via combination of evolution and divine intervention
progressive creationists
evolutionary creation
science and scripture offer 2 views of the same thing with a different emphasis
evolutionary creationists view on creation
-age of life is old
-accepts the fossil record AND origin of organisms as described by evolution
-God crated a world where things could evolve
misconception: evolution is “just a theory”
a scientific theory has undergone extensive testing and is supported by a huge amount of evidence
misconception: “evolutionists do not believe in God”
-faith is lower among scientists compared to nonscientists
about ___% of biologists believe in God and Heaven (has not changed much since early 1900s)
30%
evolutionary thinking is used in many areas such as
conservation, agriculture, pollution control, and medicine
Charles Darwin education history
-he failed at studying medicine
-graduated as a minister
-spent time with naturalists
Charles Darwin sailed around work on _________ and did what?
-H.M.S beagle
-Observed plants, animals, and fossils along the way
voyage of the Beagle:
-Darwin was tasked with mapping the South America coast
-took 5 years
why was Darwin invited on the Beagle?
as a naturalist and sophisticated company for the captain
Darwin did or did not invent evolutionary?
DID NOT; was around way before (he just described a way evolution could happen)
Darwin and atheism
- He was not an atheist, and did not rule out God
- He seems to support evolutionary creationism
philosophy of species back in Darwin’s day
- species were created perfect (so they would not evolve)
*only a few people suggested evolutions of one species to another
who was evolution first suggested by?
the Greeks, thousands of years before Darwin
philosophy of geology in Darwin’s Day
-Significant geology features were created by the flood
-Landscapes did not significantly change after flood
what did Hutton say about geology?
-recent landscapes were changing very slowly
* Example: We find river in valley, since rivers slowly make valleys by washing away dirt
people claimed that species could NOT change at all, but…
Darwin realized that he could change characteristics on purpose (selective breeding)
artificial selection:
humans have evolved species by choosing who reproduces
*Species can change
artificial selection:
humans have evolved species by choosing who reproduces
* Species can change
some individuals are better at
surviving and making offspring, so their traits will be more common in the next generation
Darwin’s idea of natural selection
natural selection accomplishes the same thing as artificial selection without human intervention
what did Darwin notice about the Galapagos islands?
*Different islands had similar finches that were slightly different on each island
*Differences seemed closely related to what finches ate (beak size differences)
Darwin’s hypothesis about the finches:
finches on all islands must have come from a common ancestor but changed to fit their environment
what book did Darwin publish after 2 decades of thoughts and experimentation
On the Origin of Species
4 observations: the fundamental principles of natural selection
1.Individuals within populations vary
2.Some variation can be passed on to offspring (inheritance)
3.Not all offspring survive
4.Survival and reproduction are not random
variant:
each different type of individual in a population
- variation passed to offspring: Darwin studied pigeons:
Fan tailed pigeons are more likely to have fan tailed offspring
*Genes allow traits to be passed to children (he did not understand how this worked)
example of observation 3: not all offspring survive
Trees make millions of seeds, but only a few sprout.
-Even fewer grow into full grown trees.
with unlimited resources, 2 elephants…
could grow to 15 million elephants in 500 years (but the environment can’t support that many)
- survival and reproduction are not random:
some variants are more likely to survive and reproduce
-individuals that survive long enough to reproduce are not random:
(4) selective pressure
non random influence on who survives and reproduces
(4) fitness
survival and reproduction of one variant compared to other variants
(4) adaptations
-traits that increase fitness
-make variant more likely to survive and reproduce
natural selection ______ new traits
CANNOT MAKE
what creates new traits?
mutations or sexual reproduction (mixes traits)
Natural selection can only select for traits that
already exist in a population
-Dodo birds went extinct because they had no traits that made them wary of hunters
* Natural selection could not select for a trait that kept Dodo birds safe from hunters since it did not exist
natural selection results in
populations that are better fits in their current environment
traits that increase survival in one environment…
may cause problems in another environment
most adaptations are tradeoffs between
success in one situation versus another
swallow example (why adaptations are a tradeoff)
North American swallows are adapted to eat flying bugs, but they must migrate in winter when all local flying bugs die
adaptations are limited
by organism’s underlying biology (MUST be modifications of existing structures and pathways)
example of pandas (how adaptations are limited by underlying biology)
pandas developed a “thumb” since they hold bamboo, but the thumb is made from a wrist bone and is a variation based on existing structures
natural selection progresses toward a goal?
NO, it has NO goal
natural selection is “blind”:
Cannot see what adaptions might be needed in future
Only adaptations that are useful NOW are selected for
natural selection in passive
no organism is choosing to adapt
we cannot determine if an adaption is helpful or not without
knowing the environment
