Earth In The Beginning • Earth formed 4.6 billions of years ago. • It was a fiery ball of molten rock • Climate was hot ; there was not any water • Early earth was lifeless
History of Life on Earth • Series of chemical events that produced the first living cell. • Life first appeared 3.5 billion years ago.
Origin of Life • Unicellular (one celled) Prokaryotes (cells without a nucleus) were the first form of life to dominate earth • Bacteria • More complex multi-cellular (many celled) eukaryotic ( cells with nucleus and organelles) organisms evolved from bacteria • 1.5 billion years ago
Clues in the Rocks • Evidence of early life have been in the discovery of fossils • Clues about how life evolved
The Geologic Time Scale • Shows the major geological and biological events in Earth’s history. • Divided into four major eras. • Cenozoic Era • Mesozoic Era • Paleozoic Era • Precambrian Era
The Cambrian Era"The Age of Trilobites" • Life exploded during this era. • Most organisms that exist today originated in this era. • Fish and invertebrates appeared n (organisms with shells) • There was no life on land
Paleozoic • Life evolves on land • First land plants appear. • Amphibians are the dominant animal during this time.
Mesozoic EraThe Age of the Dinosaurs • Dinosaurs appear during this era. • Birds and mammals appear but aren’t prominent.
Cenozoic Era • Started 65 million years ago, continues to present. • Mammals become the dominant life form on land. • Humans appeared during this era
Mass Extinction • Death of all members of many different species that is caused by a major ecological disaster. • Dinosaurs mass extinction • Caused by a large meteorite crashing to earth • Changed the climate, block the sun and caused the temperature to be very cold
Learning Experience • “The time is sixty-five million years ago. A huge meteorite has hit the Earth. Imagine that you are a dinosaur and you notice things seem different! Write a story from the point of view of your dinosaur. How do you feel? How is your environment changing? • Make an illustration to accompany your story.” • MC- 4 paragraphs • JR-3-4 paragraphs • LC-2-3 paragraphs
Learning ExperienceLife as a Fossil • MC /JR/LC-Imagine yourself as an ancient organism that has ended up in the fossil record. • Draw a picture of yourself as a fossil (you decide what your fossil would look like) and provide the following information: who were you (type of animal-create a new animal); what was your world like; what era did you live in (use textbook); how did you live; how did you die; who discovered you and what was your name. • This should be written in 2-3 paragraph (no color) • Drawing (use at least three colors)
Theory of Evolution • Evolution=Process by which living things change over time ( millions of years and not in one lifetime). • New species develop from older species as a result of gradual change
Theory of Evolution (Accelerated) • Four major points 1.Variation(differences) exists within the genes of every population or species • That is why we all look so different 2. Some species are better suited to survive (result of variation) and have more offspring 3. Favorable traits spread (thick fur, long beaks) 4. Species evolved from extinct organisms • Simply Put: CHANGE OVER TIME
Species • A group of organisms look alike and can reproduce among themselves.
Scientist-Theory of Evolution • Charles Darwin- scientist that suggested a theory of evolution that is accepted by most scientist today. • The Origin of Species (Title of Book) • Main Idea: Species Changed over time by natural selection
Lamarck’s Theory • 1st scientist to develop a theory of evolution • Proposed that traits were acquired (obtained) in a lifetime through use and disuse. • Example: Giraffes have long necks because they had to be able to reach the food in the trees. • Why is this theory false? • We can not obtain the traits that we need. Traits are inherited from parents and evolution does not take place in a lifetime.
Adaptation • Trait (s) that helps an organism to survive in its environment • Increases chances of survival
Example of Adaptation • Camouflage-Organisms ability to hide itself from predator and prey by blending in with its environment.
Examples of Adaptations • Every animal has certain features that help it "fit in" with its surroundings. • Animals who can't adapt die! (Dinosaurs) • Being able to move very quickly • Having strong claws • Having sharp teeth • Having long, curved beaks • Having keen eyesight • Having the ability to trap prey
Learning Experience • Design a magazine cover with a title related to evolution and natural selection. • 1. Give your magazine a title • 2. Decorate your magazine with pictures related to evolution. • 3.Come up with four titles of items that will be found in your magazine that is related to evolution.
Natural Selection • Survival of offspring that have favorable traits. • It is the force that drives evolution (like fuel in a car) • Evolution would not take place without the mechanisms of natural selection. What is the favorable trait in this picture?
Natural Selection • Five main elements • 1. Variation (differences in traits among individuals of species) Ex. Different wing color, hair color, height, speed and strength.
Natural Selection • 2. Struggle for Existence: • Offspring compete (try to get) for things that they need in order to survive. • Food and shelter • Some will survive and some will die.
Natural Selection • 3. Overproduction: • Species produce more offspring that can survive because many will not survive.
Natural Selection • 4. Survival of the Fittest: • Some Variations make organisms better suited for an environment. (Cold environment: fur) • These organisms are more likely to survive and reproduce.
Natural Selection • 5. Evolution of New Species: • Favorable Traits are passed onto their offspring. • Unfavorable traits disappear which can lead to the appearance of a new species.
Natural Selection • SIMPLY PUT: Survival of the fittest (best suited to the environment)
Natural Selection Output • Divide your paper into five. • Draw a picture for each of the main elements of natural selection. • Answer Question: Why is natural selection important?
Evidence of Evolution • Fossil Record provides evidence of changes that have taken place throughout Earth’s history. • Clues that support the theory of evolution
Evidence of Evolution • Fossil: are the remains or traces of ancient life; can be mineralized bones, teeth, shells, wood, or actual unaltered material from an organism. • Provide evidence of how a species has changed over time. • Ex. Horse
Evidence of Evolution • Homologous Structures: structures that are similar in structure but not function. • Provide clues that organisms evolved from the same ancestor.
Evidence of Evolution • Vestigial Structures: body structures that seem to have no function. • At one time did have function but has diminished (become less) over time due to evolution. • Ex. Wisdom Teeth
Evidence of Evolution • DNA Evidence: DNA (the genetic map of an individual) provides evidence of common ancestry. • Dog and bears are closely related because they have very similar DNA
Evidence of Evolution • Simply Put: The evidence of evolution provides proof that evolution actually takes place.
Evidence of Evolution • 1. Write a two paragraphs letter to student who is absent explaining the notes. This should be in your own words. • Include a drawing that will help to further explain what we talked about in class today.
Classification • Grouping things according to similarities, or how they are alike.
Taxonomy • Science of naming and classifying organisms. • Classification is a way of organizing information about different kinds of living things. • Makes it easier for scientist to identify newly discovered organisms.
Classification of Living Things • Classified based on shared Characteristics • Appearance (how they look) • Structure (how they obtain energy or type of cells)
Early Classification Systems • CarolusLinnaeus developed a new way to classify organisms. • Classified according to their physical characteristics. • Father of Taxonomy
Classification Levels • Seven major classification levels • Number of different kinds of organisms decrease as you move from the kingdom level to each of the next smaller levels. • From Largest to Smallest • Kingdom, Phylum, Class, Order, Family, Genus and Species