CHANGES OVER TIME

Meraki: (n.) the soul, creativity, or love put into something; the essence of yourself that is put into your work.

NORMAL CURVE (75% IS MEAN)

THE BEAGLE Dec year trip around the world 22 year old Charles Darwin was the ships naturalist

DARWIN’S OBSERVATIONS Diversity of living things Remains of ancient organisms Characteristics of organisms on the Galápagos Islands

DIVERSITY Darwin saw diversity in insects and plants throughout south America discovering many new species Species: group of similar organisms that can mate and produce fertile offspring

FOSSILS Darwin studied fossils of past organisms that resembled current organisms Sloth fossils that resembled living sloths, only much larger

GALÁPAGOS

GALÁPAGOS ORGANISMS

COMPARED TO THE MAINLAND Organisms where very similar, however they did have distinct differences Eg: iguanas on the islands had larger hands for holding on to rocks to eat seaweed where as mainland had small hands to climb trees and eat leaves

DARWIN’S THOUGHTS A small number of plant and animal species had come to the Galápagos Islands from the mainland Once on the Islands they reproduced and the offspring became different from the mainland

COMPARISONS AMONG ISLANDS Tortoises had different shaped shells from different islands

ADAPTATIONS Finches had varied sizes and shapes of beaks

ADAPTATIONS Adaptations are traits that help an organism survive and reproduces The finches beak structure helps to obtain food

EVOLUTION After Darwin’s return he spent the next 20 years thinking about his observations and talking to other scientists Darwin reasoned that plants or animals that arrived on the Galapagos Islands faced conditions that were different from those on the mainland. Darwin Hypothesized the species gradually changed over many generations and became better adapted to the new conditions

EVOLUTION (CONT.) The gradual change in a species over time is called evolution This happens to a species, and slowly over years and years Darwin did not know how the changes had happened Today this is a scientific theory, meaning it is a well tested concept that explains a wide range of observations

SELECTIVE BREADING Farmers saw similar changes with there selective breading in animals If you want fine wool, only bread sheep with fine wool. Over time you will only have sheep with fine wool. However what chooses this trait in nature?

NATURAL SELECTION In 1858 Darwin proposed that the mechanism for choosing traits naturally is called Natural Selection Natural Selection: the process by which individuals that are better adapted to their environment are more likely to survive and reproduce than others of the same species This theory was outlined in Darwin's Book The Origin of Species

FACTORS OF NATURAL SELECTION Darwin proposed that there are many factors that control natural selection Overpopulation Competition Variations

OVERPOPULATION Darwin knew that many species produce far more offspring than can possibly survive, like insects Not enough food, water, space, etc. for all of them to live So why is the world not overrun by ants?

VARIATIONS A difference between individuals of the same species is called a variation Eg. Many insect can eat foods that others of there species avoid