HW: Finish Peppered Moth Lab Monday May 1, 2017 I can: understand the principles of evolution discovered by Darwin Agenda (10) Catalyst (20) GN: Intro to Evolution (40) Peppered Moth Lab (10) IP: Evolution (5) Exit Ticket Catalyst What does gel electrophoresis do? How do strands of DNA move in electrophoresis? How have organisms changed since the beginning of time? *TURN IN UNIT 4 PACKET* HW: Finish Peppered Moth Lab

Tuesday May 2, 2017 I can: Agenda Catalyst HW: None (10) Catalyst understand the principles of evolution discovered by Darwin Agenda (10) Catalyst (20) GN: Intro to Evolution (10) Survival of the Fittest (10) IP: Evolution (15) GN: Evidence of Evolution (20) IP: Evidence of Evolution (10) Exit Tickets Catalyst What does gel electrophoresis do? How do strands of DNA move in electrophoresis? How have organisms changed since the beginning of time? HW: None

What scientific explanation can account for the diversity of life on Earth?

During his worldwide travels on the H. M. S During his worldwide travels on the H.M.S. Beagle, Charles Darwin made numerous observations and collected evidence that led him to propose a hypothesis about the way life changes over time. born 1809

Much of Darwin’s theory was developed from observations made on the Galapagos Islands.

Each island had different climates, and the tortoises on each island had different-shaped shells…but WHY? Darwin observed that the characteristics of many plants and animals varied noticeably among the different islands of the Galapagos.

Each island had different climates, and the finches on each island had different-shaped beaks…but WHY?

Darwin published his observations and theory of evolution in a book titled “On the Origin of Species” in 1859. The four main ideas that he published have held up and have been strengthened by recent evidence.

Idea #1: There is variation among members of a species.

Idea #1: There is variation among members of a species.

Idea #1: There is variation among members of a species.

Idea #1: There is variation among members of a species.

Idea #2: Some of this variation is heritable – it can be passed on to offspring. Evidence: Humans select for and breed the already-present variations that they find useful. This is called artificial selection. Example: Cabbage, Brussels sprouts, broccoli and cauliflower are all variants of the same plant.

Idea #2: Some of this variation is heritable – it can be passed on to offspring. Evidence: Humans select for and breed the already-present variations that they find useful. This is called artificial selection. Example: All dog breeds come from the same grey wolf ancestor.

Idea #2: Some of this variation is heritable – it can be passed on to offspring. Evidence: Humans select for and breed the already-present variations that they find useful. This is called artificial selection.

Idea #3: There is a struggle for existence as organisms compete over a limited amount of food, living space, and mates. Not every organism will survive and mate.

survival of the fittest Idea #4: Individuals that are better suited to their environments, or with adaptations that enable fitness, survive and reproduce most successfully. survival of the fittest = natural selection adaptation – any inherited trait that increases an organism’s chances of survival (can be anatomical/structural or behavioral) fitness – the ability of an organism to survive and reproduce in its environment

What adaptations does an arctic hare have to enable it to survive in an arctic environment?

How does a change in environment affect the fitness of the hare? When an organism’s environment changes, its fitness can change as well.

Over time, natural selection results in changes in the inherited characteristics of a population. Populations become better adapted to their surroundings. There is variation in shell color in the beetle population. Because brown beetles can blend into tree bark, they can escape being eaten. They have greater fitness and reproduce more. Over time, there are more brown beetles in the population. Evolution is change in a population over time.

Darwin’s most controversial idea: Descent with Modification Each living species has descended, with changes, from other species over time.

Darwin’s most controversial idea: Descent with Modification Each living species has descended, with changes, from other species over time. If we go back far enough in time, all living and extinct species share one common ancestor.

SURVIVAL OF THE FITTEST!

Worktime! IP: Evolution (10 minutes) Will continue on Notes 35 after

Write on your board Some dairy cows produce more milk than others. This is an example of:

heritable Write on your board Some variation is _________; it can be passed on to offspring. heritable

artificial selection Write on your board Humans breeding organisms for desirable traits is called _________. artificial selection

false; not all of them can survive Write on your board T or F: Every organism that is born survives because there is enough food, water, and shelter for everyone. false; not all of them can survive

survival of the fittest Write on your board Natural selection is also called: survival of the fittest

fitness Write on your board The ability of an organism to survive and reproduce is: fitness

F; the best-adapted to the environment survive Write on your board T or F: The strongest always survive and reproduce; they have the greatest fitness. F; the best-adapted to the environment survive

adaptation Write on your board A(n) __________ is a trait or characteristic that increases an organism’s fitness. adaptation

better adapted Write on your board Over time, populations become __________ to their environments. better adapted

Evolution is CHANGE over TIME REMEMBER: Evolution is CHANGE over TIME

Darwin argued that living things have been evolving on Earth for millions of years, and there are various lines of evidence for his claims. Fossil record Geographic distribution of living species Similarities in anatomy Similarities in embryology Biochemical similarities There is NO debate about whether evolution occurs. The only debate is about HOW it occurs.

1. Fossil record a fossil is a remnant of ancient life By comparing fossils from older rock layers with fossils from younger layers, scientists can document that life on Earth has changed over time.

2. Geographic distribution of living species A. Many distinct species look similar because they faced similar pressures of natural selection.

2. Geographic distribution of living species B. Some animals share a common ancestor but look different because they adapted to different environments. The modern-day finches of the Galapagos Islands are now distinct species – however, they all likely descend from a common ancestor that was blown off-course from the shore of South America.

3. Anatomical similarities Examination of the anatomy, or body structure, or living animals shows the existence of homologous structures. homologous structures are structures that have different functions, but developed from the same tissue species that share homologous structures share a common ancestor humans, dogs, birds, and whales share a common ancestor

3. Anatomical similarities vestigial structures are features present in modern animals that are no longer in use; give hints as to the evolution of organisms

4. Similarities in embryology Many embryos (unborn specimens) look similar during certain stages of development.

4. Similarities in embryology Many embryos (unborn specimens) look similar during certain stages of development. Similarities in embryo development show common ancestry.

5. Biochemical similarities Comparing DNA sequences reveals possible evolutionary relationships. similar DNA  similar amino acids  shared ancestry this is the BEST evidence for evolution the more similar the DNA/amino acids, the more closely related the species

This shows that ALL organisms came from one common ancestor! 5. Biochemical similarities ALL living things on Earth share the same DNA, the same ATP, and the same genetic code. This shows that ALL organisms came from one common ancestor!