Evolution Wrap Up

1. Evolution Wrap Up http://www.smithsonianmag.com/science-nature/The-Top-Ten-Daily-Consequences-of-Having-Evolved.html

2. General Topics • Describe how living organisms adapt to change • Describe different characteristics which makes living organisms unique • Explain the theory of evolution and how it is occurring around us at the moment • Explain natural selection and survival of the fittest • Describe how the fossil record is used to provide evidence for evolution • Explain human evolution, including how it is currently occurring around us at present • Discuss how humans are impacting on evolution through the actions we make, and how these actions can have unpredictable consequences.

3. Adaptions • When living things have offspring, they sometimes have mutations. • If these mutations give that animal an advantage, then that living thing has adapted. • Some living things can also adapt to change quickly. This gives them a good advantage if the temperature, water, predators or prey change quickly

4. Adaption Examples • There are rabbits and Bilbys. Both eat the same food but rabbits breed quicker. If it rains and there is more food, the rabbits have an advantage. • There are two types of finches. One has a slightly larger beak that can eat small and large seeds. The plant which makes small seeds has a major disease and no longer makes seeds. The finch with a smaller beak then dies due to no food.

5. Different Characteristics • There are two main types of cells. They are: • Prokaryotes: These are single celled organisms which have no nucleus. They do everything themselves – including digesting food, movement, getting rid of waste etc. They can live in a colony or by themselves. • Eukaryotes: These are multi celled organisms that have a nucleus. Most cells specialize to complete a certain job (like skin cell, heart cell etc).

6. Prokaryote

7. Eukaryote

8. Characteristics Cont. • Many living things reproduce through mitosis (sexual reproduction). This allows for many differences in the characteristics different living things have. • Different characteristics are needed for a healthy population. A lack of different characteristics may lead to problems. For example, European Royal Family and Pharaohs.

9. Evolution • Evolution is the gradual development of different species from a common ancestor. • It states that life on earth has changed over time. • Charles Darwin first suggested that different species of the same animal came from a common ancestor.

10. Examples • One examples can be seen in Giraffes. It’s common ancestor had a shorter neck. • However, over time some mutations occurred and gave that animal a competitive advantage. • That animal ended up replacing the shorter giraffes.

11. Other Examples • Locusts are like <insert student name  >, they eat everything around them. Sometimes locusts need to travel long distances to get to food in countries like the United States. • As such, the locusts which can travel longer distances will have an advantage and will have more offspring. • Those insects will then replace or become the dominant ones of the species.

12. Natural Selection • The idea of natural selection is that mutations or adaptions that give a living organism will mean that it will have an advantage. • That advantage will then make it more likely to become the most dominant of that species. • Living things can adapt so that they specialize in a certain food source which makes it easier to get food

13. Examples • One example of natural selection can be seen in finches. • Each finch had a common ancestor, but adapted so they got food from a different source.

14. Bower Bird • The Bower Bird has adapted to have been complex mating rituals as a result of having few animals that eat them and plenty of food. • http://www.youtube.com/watch?v=GPbWJPsBPdA

15. Fossil Record • Fossils are only found in sedimentary rocks. These rocks are made from broken down pieces of rock. This may be sand, mud, rocks etc. • The majority of plant and animal remains break down. Only those that are found in rock which are quickly covered are normally preserved for us to see at a later time.

17. Evidence • The picture shows the evolution of a horse and shows one of the legs. • Horses used to be smaller but had an advantage by being bigger and easily running away from their predators. • As horses got larger and faster, they had less problems with predators. One problem is that predators also evolve as well.

18. Human Evolution • In the 8 million years ago, the earliest ancestors of human diverged from the apes, at least a dozen humanlike species, called hominids have lived on Earth. • The process of human evolution: Monkey > Australopithecus > Homo erectus > Homo habilis > Homo sapiens (which is modern man).

19. Monkey

20. Australopithecus

21. Homo erectus

22. Homo habilis

23. Homo sapiens

24. The Time Line Of Humans

25. How did humans evolve? • Since the earliest hominid species diverged from the ancestor we share with modern African apes, 5 to 8 million years ago, there have been at least a dozen different species of these humanlike creatures. • Many of these hominid species are close relatives, but not human ancestors. Most went extinct without giving rise to other species. However, almost certainly direct ancestors of Homo sapiens. While the total number of species that existed and the relationships among them is still unknown, the picture becomes clearer as new fossils are found. Humans evolved through the same biological processes that govern the evolution of all life on Earth.

26. Human Impact on Evolution • Humans affect evolution in many different ways. Some examples are: • Global Warming • Deforestation • Urbanization • Introduction of New Species • Farming • Human Intervention

27. Examples • Warmer pole temperatures are meaning Polar Bears have shorter hunting periods to get food. • Krill (like Shrimp) is now in smaller amounts near Antarctica because of warmer sea temperatures. This highly affect the food web in the Southern Ocean (less whales, penguins, seals, fish etc)

28. Examples • Cutting down trees gives some animals an advantage. For example, Kangaroos like grassland which was not very common in Australia until humans hunted through fire. • Birds that live in cities are changing their songs so they can still hear each other • Introducing new animals (like Rats) can kill animals that never used to have predators. For example, Crabs on Christmas Island

30. Examples • In farming, humans will choose plants and animals which show the traits that they want. For example, humans will choose plants that provide more fruit that tastes better. • Humans can also spray for insects to kill them. Some of the insects will not be killed by the spray, so they become the dominant species/

31. Inheritance • Today, we will be looking at how different living organisms inherit different traits

32. Traits • Traits are individual features that every living organism has. For humans, these might be things such as hair color, eye color, skin color, being able to roll your tongue etc…… • These are determined by your genes or DNA. • The information in your DNA is stored in 46 chromosomes. You get 23 of them from your mother, 23 from your father • Different types of traits depends of different types of inheritance.

33. Glossary Book • Allele: A copy of a gene • Genotype: The genetic makeup, as distinguished from the physical appearance, of an organism or a group of organisms • Phenotype: What an organism looks like as a consequence of the interaction of its genotype and the environment • Heterozygous: Contains mixed alleles (Rr) • Homozygous: Contains the same type of allele (RR)

34. Inheritance • Each copy of a gene is called an allele. • If both alleles are the same, they are said to be homozygous. • If the alleles are different, they are said to be heterozygous. • The three types of inheritance are: • Dominant • Intermediate Inheritance • Co-Dominance

35. Inheritance • In an allele, if the letter is a capital (R) then the trait is dominant. • In an allele, if the letter is small (r) then the trait is recessive • Each individual trait is called a genotype (ie R or r). • The overall trait is called the phenotype (ie RR, Rr or rr)

36. Dominant Inheritance • Each genotype has two alleles e.g. rr, RR or Rr • Alleles can be described as a copy of a gene. • Alleles can be dominant (R) or recessive (r) • If one of the alleles is dominant, then the genotype (trait) will be the dominant trait e.g. brown eyes.

37. Intermediate Inheritance • For intermediate inheritance a heterozygous genotype creates an intermediate phenotype. • Neither allele is dominant

38. Intermediate Inheritance - Carnations • A classic example of this is the colour of carnations. • R is the allele for red colour • W is the allele for no colour • RR flowers appear red. • WW flowers are white. • RW are pink.

39. Co-Dominant Inheritance • In Co-dominance, neither phenotype is recessive. • Instead, the heterozygous individual expresses both phenotypes. • A roan horse has co-dominant follicle genes, expressing individual red and white hairs.