Review of evolution 1/2

• Darwinism


  the theory of the evolution of species by natural selection advanced by Charles Darwin.

  
  

  came from galapagos island bird beaks
• Lamarckism


  First proposed by Lamarck, the theory of evolution through the inheritance of acquired characteristics in which an organism can pass on features acquired during its lifetime.

  - false, darwin proved this to be wrong. Characteristics are developed in the population, not individual level
• Evolution


  Change in a population over time; genes in the gene pool

  
  

  Evolution is NOT random, due to genetic variations either surviving and doing well or dying out, adaptations spread
• Tenets of Evolution


  - Survival is not random. The organisms within the species that survive have a variation in a trait that gives them an advantage.

  
  

  - More offspring are produced in a generation than will survive to reproduce.

  
  

  - There must be genetic variation within the population
• Island Biogeography


  the study of the species composition and species richness on islands

  
  

  shows how species travel from one place to another, creates geographical isolation
• Proofs of Evolution


  biodiversity,

  biogeography,

  fossil record,

  embryology,

  comparative anatomy,

  molecular evolution
• Genetic drift


  A change in the allele frequency of a population as a result of chance events rather than natural selection.
• population bottleneck


  really similar to genetic drift - jsut a big dropoff
• Nonrandom mating


  mating between individuals of the same phenotype or by those who live nearby
• Mutation


  we all fricking know this if you don't just drop out of apex bio. im not trying to be mean just if you don't know, just drop out, genuinely

  but

  Any change in the DNA sequence of a cell - good ones are adaptations
• Fitness


  at level of being able to reproduce
• Gene Pool


  Combined genetic information of all the members of a particular population
• Gene flow


  movement of alleles from one population to another
• Equilibrium


  a state in which opposing forces or influences are balanced.
• Geographic Isolation


  different place
• Temporal Isolation


  different time of year
• Behavioral Isolation


  different mating way
• analogous structures


  Body parts that share a common function, but not structure

  
  

  i.e bones in limbs for human/cat - both used to move around and do whatever we do with our hands but structure is mucho different

  
  

  not common ancestor

  
• vestigial structures


  remnant of a structure that may have had an important function in a species' ancestors, but has no clear function in the modern species.

  
  

  tail bone - ancestors had tails, used it. we dont - common ancestor
• Convergent evolution


  Process by which unrelated organisms independently evolve similarities when adapting to similar environments

  
  

  dolphin & shark - both fins not evolved from same common ancestor
• Divergent evolution


  when two or more species sharing a common ancestor become more different over time

  
  

  same ancestor -> same item, different use
• Microevolution


  evolutionary change within a species or small group of organisms, especially over a short period.

  
  

  Microevolution is likely to occur when there are small populations, sexual selection, mutations, gene flow, and natural selection.
• Macroevolution


  Macroevolution occurs above the species level to create new a taxonomic level - SPECIATION
• Modern synthesis
• Population bottleneck


  a type of genetic drift in which population size is sharply reduced due to some catastrophic event
• Founder effect


  change in allele frequencies as a result of the migration of a small subgroup of a population

  
  

  - i.e bettas in a pond that separated & lets j say one group got a labyrinth bladder while other didn't thats the difference, geographical isolation

  this example sucks cause i came up with it 1, 2 most (all?) betta have labyrinth bladders which let them get air from not water ik really cool
• Speciation


  the formation of new and distinct species in the course of evolution.
• Adaptive radiation of species

  whenever you have a number of species that has adapted into different niches by niche partitioning

  
  

  a rapid increase in the number of species with a common ancestor

  - Just making of new forms, going from one original species to a bunch branching off

  - Often from change in environment, new resource available

  - Like the darwin birds
• Fossils and Evolution


  show the previously living species are similar to but different from species that are alive today, shows many species have become extinct; show evolutionary changes in groups of organisms

  
  

  just change over time in bone structure
• Selective pressure


  environmental conditions that select for certain characteristics of individuals and select against other characteristics
• acquired variation


  no two members of a species are alike, many different traits
• genetic recombination


  The regrouping of genes in an offspring that results in a genetic makeup that is different from that of the parents.
• Systemics/Phylogeny


  the study of the evolutionary history of a group of organisms
• Cladogram


  shows revolutionary relationships through common ancestors. Sharing a more recent common ancestor mean they are more closely related.

  
  

  nodes show the different traits

  
• Asexual Reproduction


  Reproduction with one parent, faster, and results in lots of offspring with less genetic variation
• Sexual Reproduction


  Reproduction with two parents, slower, and results in fewer offspring with genetic diversity
• Meiosis


  Cell division producing 4 haploid gametes, reducing chromosome number, and allowing genetic diversity
• Zygote


  Diploid cell formed by the fusion of two haploid gametes during sexual reproduction

  
• Gametes


  Sex cells (sperm in males, egg in females) used to create a zygote

  
• Spermatogenesis


  Process in males producing 4 haploid sperm cells through meiosis