Evolution Vocabulary

1. Evolution Vocabulary 3.a. Analyze how adaptations to a particular environment (e.g. desert, aquatic, high altitude) can increase an organism’s survival and reproduction and relate organisms and their ecological niches to evolutionary change and extinction. (DOK 3)

2. These words can be found in sections 1, 2 & 3 in Chapter 8 in the book • Species • Fossil • Adaptation • Evolution • Scientific theory • Natural selection • Variation • Homologous structures • Branching tree • Petrified fossil • Mold • Cast • Relative dating • Radioactive dating • Half-life • Fossil record • Extinct • Gradualism • Punctuated equilibria

3. These words are not in the book but will be on your vocabulary quiz Survival of the fittest – a struggle for life in which only those organisms best adapted to existing conditions are able to survive & reproduce Bioluminescent – emitting light Echolocate – determining the location of something by measuring the time it takes for an echo to return from it Inbreeding – breed from closely related animals

4. These words are not in the book but will be on your vocabulary quiz Migration – the movement from one location to another Mutualism – a relationship between organisms of different species in which both organisms benefit from the association

5. The Theory of Evolution by Natural Selection

6. Background Information December 1831, the British ship HMS Beagle set sail from England on a 5 year trip around the world Charles Darwin on board Became ships naturalist (a person who studies the natural world) His job was to learn as much as he could about the living things he saw

7. What did he find? Observed plants and animals he had never seen before

8. Voyage of The HMS Beagle

9. Darwin’s Observations Diversity of living things The remains of ancient organisms (fossils) The characteristics of organisms on the Galapagos Islands

10. Diversity Scientists have identified more than 1.7 million species of organisms on Earth A species is a group of similar organisms that can mate with each other and produce fertile offspring

11. Diverse Organisms on Earth

12. Fossils A fossil is the preserved remains or traces of an organism that lived in the past Darwin saw fossil bones that resembles creatures living on the islands, but the fossils were different in size

13. Fossils

14. Galapagos Organisms Giant turtles/tortoises Land turtles These organisms didn’t live in England Darwin compared the organisms from the Galapagos Islands to organisms in England & other places He found many similarities and differences

15. Galapagos Organisms

16. Comparisons to South American Organisms Many similarities between South American organisms and the organisms found on the Galapagos Islands Birds, including hawks, mockingbirds, & finches, resembled birds in South America Plants were also similar

17. Differences Iguanas in South America had small claws to climb trees where they ate leaves Iguanas on the Galapagos Islands had large claws that allowed them to grip slippery rocks where they fed on seaweed

18. Iguanas

19. Darwin’s Hypothesis From his information, Darwin hypothesized that a small number of different plant and animal species had come to the islands from South America They might have been blown out to sea during a storm or set adrift on a fallen log Once the plants and animals reached the islands, they reproduced Eventually, their offspring became different from their mainland relatives

20. Classwork Assignment • With a partner, list adaptations some animals have made • Animals who live in the desert • Animals who live deep in the ocean • Animals who live at high altitudes • Animals who live in very cold climates

21. Comparison among the Galapagos Islands • As Darwin traveled to different islands, he noticed many differences among organisms • Example: tortoises on each island had different shaped shells • A government official told Darwin that he could tell which island a tortoise came from just by looking at the shape of its shell

22. Galapagos Islands

23. Adaptations • The finches on the islands were noticeably different as well • Most obvious difference: sizes and shapes of the birds’ beaks • Each showed that it was well suited for the life it led • Finches who ate insects had narrow, needle-like beaks • Finches who ate seeds had strong, wide beaks

24. Galapagos Finches

25. Adaptations • Beak shape is an example of an adaptation • An adaptation is a trait that helps an organism to survive and reproduce • Other adaptations: • Some plants are poisonous or have a bad taste • Some plants have bright colors to attract insects

26. Evolution • Darwin spent 20 years after his return from the voyage consulting with other scientists and gathering information • Darwin’s reasoning: • That plants and animals that arrived on the Galapagos Islands faced conditions that were different from those on the mainland. The species gradually changed over many generations and became better adapted to the new conditions

27. How did evolution occur? • Darwin did not understand how evolution occurred • He studied other examples of changes in living things to help him better understand • Offspring of animals produced by selective breeding • He bred pigeons with large, fan-shaped tails • By repeatedly allowing only those with many tail feathers to mate, breeders had produced pigeons with 2 or 3 times the usual number of tail feathers • Darwin thought that a similar process occurred in nature • But what process

28. Natural Selection The process by which individuals that are better adapted to their environment are more likely to survive and reproduce than other members of the same species Darwin described this theory in his book The Origin of Species.

29. Factors that identify natural selection Overproduction Competition Variations TURN TO PAGE 257: Look at the picture at the top of the page

30. Overproduction Most species produce far more offspring than can survive In many species, so many offspring are produced that there are not enough resources – food, water & living space –for all of them Example – many female insects lay thousands of eggs; if all newly hatched insects survived, they would soon crowd out all other plants and animals

31. Variations As you learned in genetics, members of a species differ from one another in many of their traits Any difference between individuals of the same species is called a variation Example – certain insects may be able to eat foods that other insects of their species avoid; the color of a few insects may be different from that of most other insects in their species

32. Competition • Since food and other resources are limited, the members of a species must compete with each other to survive • Competition does not always involve direct physical fights between members of a species • Instead, competition is usually indirect • Example – many insects do not find enough to eat; others are caught by predators • Only a few insects will survive

33. Selection Turn to page 258: look at the picture at the top of the page Some variations make individuals better adapted to their environment Those individuals are more likely to survive and reproduce Their offspring may inherit the helpful characteristics The offspring, in turn, will be more likely to survive and reproduce, which passes on to their offspring After many generations, more members of the species will have the helpful characteristics

34. Selection The environment has “selected” organisms with helpful traits to become parents of the next generation Darwin proposed that, over a long time, natural selection can lead to change. Helpful variations may gradually accumulate in a species, while unfavorable ones may disappear

35. Environmental Change A change in the environment can affect an organism’s ability to survive, and can lead to selection Example: monkey flowers are a type of plant. Most monkey flowers cannot grow in soil that has a high concentration of copper. However, because of genetic variation, some varieties of monkey flower now grow near copper mines, in spite of the copper in the soil

36. Environmental Change • How could this have happened? • When the soil around a mine first became contaminated, a small number of monkey flower plants may have been able to survive in the high level of copper. • These plants grew and reproduced • After many generations, most of the seeds that sprouted in the soil produced monkey flowers that could withstand the copper

37. Evidence of Evolution

38. Does natural selection occur today? • Yes • Example: what happens when pesticides are used to kill harmful insects such as cockroaches? • When a pesticide is first used in a building, it kills almost all the insects. • But a few insects have traits that protect them from the pesticide • These insects survive • The surviving insects reproduce & some of their offspring inherit the pesticide protection • Every time the pesticide is used, the only insects that survive are those that are resistant to the harmful pesticide • The development of pesticide resistance is one type of evidence that supports Darwin’s theory of evolution

39. Interpreting the Evidence Fossils, patterns of early development, and similar body structures all provide evidence that organisms have changed over time

40. Similarities in Early Development Scientists also make inferences about evolutionary relationships by comparing the early development of different organisms Suppose you were asked to compare an adult fish, salamander, chicken, and opossum You would probably say they look quite different from each other However, during early development, these 4 organisms are similar

41. Early Development Turn to page 263: Look at the early development of the opossum, chicken, fish and salamander During the early stages of development all 4 organisms have a tail and a row of tiny slits along their throats. These similarities suggest that these vertebrate species are related and share a common ancestor

42. Similarities in Body Structure • This is how Darwin cam to understand that evolution had occurred on the Galapagos Islands • An organism’s body structure is its basic body plan • Fish, amphibians, reptiles, birds, and mammals all have a similar body structure • An internal skeleton with a backbone

43. Similarities in Body Structure

44. Similarities in Body Structure This is why scientists classify all five groups of animals together as vertebrates All of these groups probably inherited a similar structure from an early vertebrate ancestor that they shared TURN TO PAGE 264: Look at the picture at the top of the dolphin, bird & dog

45. Similarities in Body Structure • Sometimes scientists find fossils that support the evidence provided by homologous structures • Example: scientists recently found fossils of ancient whale-like creatures • The fossils show that the ancestors of today’s whales had legs and walked on land • This evidence supports other evidence that whales and humans share a common ancestor • What do you think?

46. Review • Darwin’s theory of evolution: • Natural selection • Survival of the fittest • Adaptation to environment • Variation in species • Natural selection: over time advantageous traits will be found in more of the population • Biological theory of evolution: characteristics of simpler life-forms can be found in more complex life-forms • Trilobite fossils from different periods show small changes in appearance in response to environmental change

47. Review • Organisms which are more favored in an environment are more likely to survive • Adaptations in desert: • Small animals burrow into the ground during the day to avoid the sun’s heat and emerge only at night when temperatures are lower • Some plants have long taproots, enabling them to penetrate the water table deep within the ground • Many mammals have long tubes in their kidneys and produce highly-concentrated urine to conserve water • Adaptations in aquatic environment • Plants have broad leaves that float near the surface to access sunlight

48. Review • Adaptations that allow birds to fly: • Feathers, wings, hollow bones • Adaptations of crocodiles: • New sets of teeth grow in to replace lost teeth • Adaptations to survive in the taiga: • Needles do not need to be replaced every spring, increasing the amount of energy available for the short growing season • Adaptations of deep ocean organisms: • Able to withstand the high pressure of the water at extreme depths, so when brought to the surface, their bodies cannot cope with the relatively low pressure

49. Review • Adaptation of camels in the desert: • 2 rows of long eye lashes • Adaptation of giraffes: • Longer necks • Adaptation of mating in birds: • Females generally choose to mate with the “showiest” males • Adaptation of plants in areas with little sunlight: • Large leaves

50. Review Sponges are unable to move and can reproduce sexually or asexually Bacteria can display the most significant adaptations to their environment in the shortest period of time What will likely happen to a species that lacks the variation necessary to adapt to a changing environment? Adaptation is a term that describes a specially developed characteristic that enables an organism to live in a specific environment