Slide 1 - Evolution Change in species over.

Slide 2 People used to believe: Species are designed by a divine creator (aka God). Are fixed (aka unchanging). In other words, species have not changed over the years. False belief Earth is only 6000 years old. Earth is actually 4.6 Billion Years Old. Only a few scientists questioned the biblical story of creation or the belief that species were fixed and perfect a century before Darwin. In the mid-1700s, the study of fossils let some scientists to believe that

Slide 3 Charles Darwin came up with the theory of evolution Slide 3 Charles Darwin came up with the theory of evolution! He Lived in the 1800s. . Ideas by Charles Darwin are the basis for modern evolution.

Slide 4 - Darwin’s Voyage 1831 at age 22 Darwin took a job as a naturalist (Person who studies nature such as plants and animals) on the English ship HMS Beagle. A surveying ship on a mission to chart poorly known stretches of the south American coastline.

Slide 5 - Darwin’s voyage on the Beagle He started his trip in England and sailed all over the world.

Slide 6 - Galapagos Islands He is known for his stop in the Galapagos Islands. He studied each Island in the chain and found species were very similar, but unique compared to species in South America, which is only 500 miles away. He discovered that many species were unique to the islands but similar to species elsewhere. These observations led him to consider that species can change over time.

Slide 7 - Galapagos Tortoise Much bigger than tortoises on South America. More food in the Islands compared to the mainland. Galapagos tortoises are the largest on Earth, differing from other tortoises in body shape and size.

Slide 8 - Galapagos Iguana Island Iguanas have claws Mainland Iguanas don’t have claws. Claws allow iguanas to grasp onto rocks in the ocean. Mainland iguanas eat on land. Galapagos marine iguanas eat algae from the ocean, an unusual food source for them. Their large claws help them cling on to slippery rocks.

Slide 9 - Galapagos Finches Galapagos finches have different beaks than mainland birds, because they feed on different food. The beak of this Galapagos finch is adapted to feed on cacti.

Slide 10 – Species Organisms of the same species have: Similar traits + Reproduce + Produce fertile offspring. Horse + Donkey = Mule Mule cannot reproduce Thus, Horse and Donkey a separate species even though they can have offspring.

Slide 11 Natural Selection What causes species to change (aka evolve) Slide 11 Natural Selection What causes species to change (aka evolve)! Giraffes eat tree leaves. If short giraffes can’t reach the leaves, they will starve and die. Only tall giraffes will survive to reproduce. Since they have tall genes, their offspring will be tall too. This is what drives populations to change, “Survival of the Fittest!

Slide 12 Before the Industrial Revolution Birds eat Peppered moths Slide 12 Before the Industrial Revolution Birds eat Peppered moths. Before industrial revolution tree had light bark. Since dark moths stood out, they were eaten by birds. Light moths population increase! Dark moths population decreased!

Slide 13 After the Industrial Revolution Soot and ash pollution from industry covered trees. Tree bark became darker. Dark moths no longer stood out, but white moths did! Light moths population decreased! Dark moths population increased!

Slide 14 - Evidence of Evolution Fossils Adaptations Anatomy Embryology Biochemistry

Slide 15 - Fossils Showed that whale ancestors once lived on land Slide 15 - Fossils Showed that whale ancestors once lived on land. Scientists know this because whales still have a hind-leg bone inside of them which is meant for walking, not swimming! The hind-leg one currently has no use in the whale!

Slide 16 - Adaptations Any trait that increases an organisms chances for survival. Structural Physiological Wax-Coated Leaves prevents evaporation Evolves RAPIDLY

Slide 17 - Structural Adaptations Mimicry Camouflage

Slide 18 - Mimicry Mimic = to copy someone When one species resembles another species.

Slide 19 - Camouflage Matching in color with surroundings!

Slide 20 - Anatomy Homologous Structures Analogous Structures Vestigial Structures

Slide 21 - Homologous Structures Homo = Same Same structures between species. Come from common ancestor! Although the bones are modified for their specific function, the basic arrangement of the bones in each limb are similar. Scientists view such structural similarities as evidence that organisms evolved from a common ancestor.

Slide 22 - Analogous Structures Bird and Bugs both fly, but wings are a different structure. Bird Wings = Bone (mainly proteins) Bug Wings = Chitin (mainly carbohydrates) The structural and functional similarities of a body feature doesn’t always mean that the two species are closely related. You can compare the wing of a butterfly and a bird. Bird and butterfly wings are not similar in structure, but are in function. The wings of birds and insects evolved independently of each other in two distantly related groups of ancestors. Although analogous structures don’t shed light on evolutionary relationships, they do provide evidence for evolution. For example, insect and bird wings evolved separately when their different ancestors adapted to similar ways of life. Bones are the framework of bird wings and chitin composes the insect wings.

Slide 23 Homology Versus Analogy

Slide 24 - Vestigial Structure A body structure in a present-day organism that no longer serves its original purpose, but was probably useful to an ancestor. A structure becomes vestigial when the species no longer needs the feature for its original function, yet it is still inherited as a part of the body plan for the species. Whale ancestors lived on land and walked, so they needed a hind-leg bone. Whales still have this structure inside of them, but don’t use it because they live in the ocean now and swim.

Slide 25 – Human Vestigial Organ Appendix

Slide 26 Vestigial Structure Examples: Ostrich Wings Mole Rat Eyes Mole rats have a flap of skin that covers their eyes. They are blind but yet they still have eyes. Ostriches have wings but yet wings but yet they don’t fly. Their ancestors probably foraged for food and nested on the ground. As a result, over time, the ostrich became very large and unable to fly.

Slide 27 – Embryo The first stage of development.

Slide 28 – Embryology Compares the embryos of different species Slide 28 – Embryology Compares the embryos of different species. Scientist have found they look alike. All have a gill pouch and anal tail.

Slide 29 - Can you tell which will become a chicken. Cat. Bat. Snake Slide 29 - Can you tell which will become a chicken? Cat? Bat? Snake? Human? Possum? All look the same.

Slide 30 – Which one is a cat? Can you tell yet?

Slide 31 – What about now? Which one will turn into a cat?

All these organisms evolved from the same common ancestor

Slide 33 - Biochemistry Some organisms have similar DNA sequences.

Slide 34 - For Example: Versus Chimpanzee Gorilla

Slide 35 - For Example: Versus Chimpanzee Rose Bush