Evolutionary Thinking Flashcards
what do the nodes in the phylogentic trees repersent?
an evolutionary branch or speciation event (could show when species’ were last related to each other)
what are homologous traits?
traits that are similar to one another due to shared ancestory.
what is descent with modification?
the idea that species change over time, give rise to new species, and share a common ancestor
what is evolution a process of? and what does that tell us about characteristics of ancestral species
- process of descent with modification
- characteristics of ancestral species are modified (mostly by natural selection) as the descendants over time face different environmental challenges
what is homology
similarity resulting from common ancestory
What is “Evo-Devo”?
- evolutionary development
- looks at how changes in ambryonic development during single generations relate to the evolutionary changes that occur between generations
if 3 different species all had the capacity to fly, does that mean that their wings are all homologous traits? Explain
- no
- would not be homolgous, since they didn’t have the traits come from a common ancestor
- this is an evolution of similar traits in response to similar selective pressures, but completetly independent of evolutionary lineages known as convergent evolution
what is convergent evolution?
similarities that result from populations being exposed to similar selective pressures.
what is a “sister group”
the group of a species that evolved from the same common ancestor
why would the analysis of nucleic acids be helpful in describing the conservation of genes in the genome?
could tell us which genes in the genome are conserved over evolutionary time, due to the importance of their function to life, that the genes will evolve rly slowly due to being functionally constrained
what are ribosomal RNA in humans an example of?
- genes that are conserved and take a while to evolve
- changes occur so slowly in these genes
what are the three domains of evolution?
Archaea, bacteria, Eucarya
what do species that resemble each other found on different continents mean?
- one hypothesis: long distance dispersal
- one hypothesis: Pangea, until the continents drifted apart, animals were together until seperated by this
what is phenotypic variation?
within a population important traits will vary among individuals
what is fitness?
variation in surivival and reproduction.
what is covariation between trait variation and fitness variation mean together?
individuals will particular traits values leave more offspring to the next generation
what is phenotypic selection?
individuals who have traits that are more beneficial to the population, will be more successful in leaving offspring for future generations
what can phenotypic selection drive?
evolutionary change
what happens if a trait does not exhibit a heritable feature in terms of natural selection
it can’t be passed on or be involved with natural selection
what are the four conditions of natural selection to cause evolution
- phenotypic variation
- fitness
- covariation between trait variation and fitness variation
- phenotypic selection
what is artifical selection?
the evolutionary process in which humans consciously select for or against particular features in organisms (ex. domestication of the dog)
what is environmental change a driver of?
evolutionary change
what is one important anthropogenic impact humans have had on species around the world?
the spread of species around the world
what do invasive species do to native species in a habitat?
- confront native species with new predators, new competitors, and sometimes new food sources
- an example is the soapberry bug (pierce protective covering of fruit to eat the seeds inside)
- the soapberry bugs help to show that we can observe natural selecition in action over much shorter time frames than thought possible
