Unit 9 Vocabulary

Unit 9 Vocabulary1. Lamarck- naturalist who proposed that organisms evolved by passing acquired traits onto offspring

Unit 9 Vocabulary2. acquired characteristics- traits that arise during an organism’s lifetime (not genetic) and are not passed onto offspring

Unit 9 Vocabulary3. Darwin- naturalist who said that organisms evolve through natural selection

4. inherited characteristics- traits that are passed from parents to offspring through genes; what natural selection acts upon

Unit 9 Vocabulary6. artificial selection- selective breeding by humans for desirable traits; may produce organisms that are poorly adapted to their environment

Unit 9 Vocabulary7. evolution- change over time, especially of a species

Unit 9 Vocabulary8. population- a group of organisms of the same species living in the same place

9. Gene pool- all of the genes found in a population

Unit 9 Vocabulary10. adaptation- a characteristic that increases an organism’s ability to survive & reproduce

11. survival of the fittest- the idea that individuals who are well-suited to their environment (fit) are more likely to survive and reproduce than other individuals (natural selection)

Unit 9 Vocabulary12. mutation- a change in DNA; leads to variation and new traits in a population

13. morphological adaptation- structural adaptation

Unit 9 Vocabulary

14. physiological adaptation- adaptations of cells & body systems

Unit 9 Vocabulary

15. behavioral adaptation- adaptations of reacting to the environment

Unit 9 Vocabulary

16. theory- an explanation that is supported by a large body of evidence; ex: evolution, cell theory17. law- describes a set of relationships; ex: law of gravity18. hypothesis- an educated guess that explains observations; testable

Unit 9 Vocabulary

19. gene frequencies- the proportion of a particular allele in a population

20. evidence for evolution- compares species, helping scientists to understand how species are related and how they originated over time

Unit 9 Vocabulary

20a. comparative anatomy- the relative body features of different species; used to determine how closely or distantly related species are

20b. homologous structures- a feature found in different species that arose in a common ancestor

Unit 9 Vocabulary

20c. comparative embryology- studying the embryos of different species to determine the degree of relationship between species

20d. comparative biochemistry- studying the DNA and other biological molecules of different species to determine the degree of relationship between species

Unit 9 Vocabulary

21. fossils- impressions or casts left behind by a prehistoric organism; provides evidence of the species that have lived on Earth and when they lived

Unit 9 Vocabulary

22. Evolutionary processes:a. more offspring are born than can surviveb. individuals have variationsc. some individuals reproduce more than others

Unit 9 Vocabulary

23. recombination- shuffling of genes in new combinations through crossing over or sexual reproduction

Crossing Over:

Sexual Reproduction:

Unit 9 Vocabulary

24. variation- differences in the traits seen in a population

Unit 9 Vocabulary

25. species- a group of organisms of a single type that can reproduce

26. subspecies- a particular variation seen within a species that may, over time, become a different species; ex: Cannis lupus familiaris (the dog) is a subspecies of Cannie lupus (the gray wolf)

27. speciation- the evolutionary process by which new biological species arise

Unit 9 Vocabulary

28. gametic isolation- separation of individuals and their genes based upon how different eggs and sperm refuse to unite due to their identification markers

Unit 9 Vocabulary

29. geographic isolation- separation of individuals and their genes due to physical barriers

30. temporal isolation- separation of individuals and their genes due to mating at different times of the day or year

Unit 9 Vocabulary

31. behavioral isolation- the separation of individuals and their genes based upon difference in their behavior, such as mating habits

Unit 9 Vocabulary

32. habitat isolation- the separation of individuals and their genes based upon how they occupy different habitats and do not encounter each other

33. mechanical isolation- the separation of individuals and their genes based upon how the reproductive parts of the different individuals do not fit together

Unit 9 Vocabulary

34. punctuated equilibrium- model that shows how a lot of evolutionary change takes place in short periods of times that are tied to speciation events; evolution with few transitional forms

Unit 9 Vocabulary

35. gradualism- model that shows how large changes in organisms build slowly over time; seen in both the fossil record and geology; evolution with many transitional forms

36. phylogenetic tree- a branching diagram that shows evolutionary relationships between species

Unit 9 Vocabulary

37. random genetic drift- a shift in allele frequencies due to chance

Unit 9 Vocabulary

38. lethal- deadly; 1 or 2 lethal alleles can kill an organism

39. interbreeding- capable of reproducing together

Unit 9 Vocabulary