Unit 2 Test Flashcards
Skill of describing events
-gather information about events or processes
-Can be quantitative: measurable or countable
-Can be qualitative: describable and not numerical
Observation
Conclusion or deduction based on observations, from given evidence
Inference
Evolution is just a theory, true or false
True
Broad explanations for wide range of phenomena, three must be strongly, supported by different forms of evidence to be supported
Scientific theories
Possible explanation/answer to a scientific question
Hypothesis
Well tested explanation
Theory
How is evolution supported?
- Fossil record
- Geographic distribution of living things (biogeography)
- Atom evidence
A) homologous body structures
B) vestigial limbs
C) similarities in early development - Molecular DNA
Traces of dead organism, such as footprints, insects, bones, leaf impressions, etc.
Fossils
What does a fossil record show?
A sequential appearance and disappearance of species, new species appeared gradually, with species becoming more complex overtime
What does the fossils found in the rock tell us?
Two things:
1. Looks.
2. How long ago they existed, deeper=older
Why is the fossil record incomplete?
Because very few species turn into fossils, most decay away
What happens when forming fossils?
Not all parts of the animal become fossilized (makes it hard to know some details)
What determines age of a fossil?
Radioactive decay
Age of a fossil can be determined through radiometric dating (determining the age of layer of fossil found in)
absolute age
Age of fossil is determined by comparing it to other fossils
Relative age
Bones that contain traits of ancestral groups and descendant groups, link new species to old species
Transitional fossils
Study of geographic distribution of species overtime
Biogeography
Independent development of similar structures and organisms that are not directly related
-live in similar environments, but in different locations
Convergent evolution
What is the supporting evidence for biogeography evolution?
-similar animals on each continent live in similar ecological conditions
-Exposed to similar pressures of natural selection, because of this different animals ended up evolving similar characteristics
Ancestral species gives rise to a number of new species that are adapted to different environmental conditions and are less alike
-occurs when species colonize new environment
Divergent evolution
Occurs when species colonize new environment
Adaptive radiation
Each living organism has descended with changes from other species overtime
Descent with modification
All of the things were derived (originated) from common ancestor
Common descent
Structures from different organisms that have different mature forms, but come from same embryonic origin
Homologous structures
-homo=same
-logous=information
(Same structure inside, same development in embryo, but different functions on outside, evidence of common ancestors)
Structures that are present in organism, but do not serve any function (remnants of evolutionary past)
Vestigial structures
Structures that look similar on outside and have same function, but have different structure and development on the inside (different, no evolutionary relationship)
Analogous structure
What is embryology?
Study of developing embryos, evidence that supports evolution
Why does embryos support evolution?
- Embryos of vertebrates are very similar during early development
- Common cells and tissue grow similar ways, produce homologous structures
- Common genes
- Molecular DNA evidence (similar DNA and common ancestor)
What are humans most related to?
Chimpanzees
Origin of species
Speciation