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1
Q

Explain the statement “Science is a process.” Briefly provide an historical example to
substantiate this statement

A

science is a process means that science is everchanging and is always developing. for example, lamark vs darwin theory. lamark came before darwin and his postulates were wrong but they provided a basis for darwin. same with modern postulates. ex darwin said individuals in population vary, but in relatity populations evolve, not individuals

2
Q

What is the most important scientific contribution of Darwin and Wallace?

A
  • came up with mechanism by which evolution happened (Natural selection); evolutionary mechamims of natural selection
  • descent with modifications
  • evolution is a fact, natural selection is a theory
3
Q

What are the two main points generated from the ‘Origin of Species?

A
  1. evidence that the many species of organisms currently in existence are descendants of different and now extinct ancestral species. we are descendants of what came before us
  2. Natural selection: the mechanism for evolution; theory
4
Q

What are the modern postulates of the ‘Theory of Evolution by Natural Selection?

A
  • Populations evolve: changes in allele frequencies over time in a popultation
  • Traits are heritable: natural selection occurs when individuals with certain alleles have increased fitness. (number of individuals you can provide to next generation) An adaptaion is a genetically based trait that increases an individuals fitness in a particular environment
  • evolution by natural selection is not progressive: animals do not do things for the good of the species, and not all things are adaptive. all adapations are constricted by tradoffes as well as genetic and historical factors
5
Q

Are all adaptations positive?

A

No. adaptations are genetically based trait that increases an individuals fitness in a particular environment. They are constricted by tradoffes as well as genetic and historical factors. depend on other facots. occur whether positive or negative

6
Q

Distinguish meanings of evolution as fact and evolution as theory.

A

Fact- we know that evolution occured
Theory- the mechanism by which evolution occurs (natural selection) is a substatiated thory

7
Q

Describe why the study of evolution is an integrated science.

A
  • basis for life
  • helps us undertsand how things are changing
  • science is a process. It is okay to be wrong
8
Q

physchology of categorization

A

Category- a set of entities that are equivalent in some way. usually the items are similar to one another
Psychological essentialism- the belief that members of a catergory have an unseen property that causes them to be in the category and to have the properties associated with it
Typicality- the difference in “goodness” of category members, ranging from the most typical (prototypes) to boderline members

9
Q

what is evolution

A
  • a species within a group has a change
  • the species as a whole adapts due to the environemt
  • a population level phenomenon
  • change in allele frequency in a population. change in a population that we can observe over time
  • agood example: fraction of people with blue eyes in world has decreased 15% in last centery (this is a change in allele, not impacted by other things like nutrition, healthcare, pollution)
10
Q

what cn evolution tell us?

A
  • this is complicated
  • why species are good at what they do
  • based on theory of natural selection
11
Q

charles darwin

A
  • origin of speices by natura; selection
  • galapagoes finches and tortises
    -observational studies (from earth worksm to pigeons to so on)
12
Q

alfred wallace

A
  • decreased social staus compared to darwin
  • collected oragnisms from indonesia
  • similar finding to darwin: observed how things are similar but different
13
Q

darwins postulates

A
  1. indivuduals in a population vary
  2. some of the variation is heritable
  3. individuals overreproduce (beyond replacement numbers) (ex. sea turtles)
  4. the varients differ in their likelihood to survive and reproduce
13
Q

what is fitness

A

how good a genotype is at leaving offspring in the next generation relative to other genotypes
- the number of individuals you can provide to the next generation

13
Q

is evolution progressive

A
  • no
  • evolution by natural selection is not progressive. animals do not do things for the good of the species, and not all traits are adaptive.
  • all adaptaions are constrained by trade offs as well as genetic and historical factors
14
Q

greek philospheres

A
  • science is a proces
  • species are unchanging to recognized species, but not change to physocal forces created universe as oppoed to super natural to mechanistsics process but not gradual
15
Q

rationalism

A
  • understanding the world in terms of cause and effect
  • ex gravity to apple falls to must have an effer to gravity is the efect
16
Q

lamark

A
  • compared current species with fossils
  • several lines of apparent descent
  • has to ideas: 1) use and discue: body parts that are used a lot become larger and stronger 2P inheritance of aquired characteristics idea
    …… but that is wrong
17
Q

epigenetics

A
  • epigentics has a modern but wrong application to support lamark
  • epigeentics is a non genetics phenomenoa that takes places inside living cells that may alter development ( its a response to chnage )
18
Q

evidence to supprt natural selection

A
  • vestigial characters (trait that is left over but no longer useful), evidence that speices characters have changed through time

-homologus characters (same structure in multiple organisms), evidence for phylogenetics and relatedness among species, ontogeny repitulates phyogeny, bio genetics and the phylotypic period (ex. developmentl homology, same structre but different because of environemental influecne; changes in allele based on environmetn)NOTE: analygous characters may look similar bt have different function

-fossils: mary anning; evidence for two factors: species go extinct and transitional forms over time

18
Q

lyell

A
  • uniformitarism: undertsand geological features by studying processes todya- process that creates canyon, canyon can be seen today
  • extensim of rationalism
  • cause nd efect