* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download Changes in Living Things Notes
Survey
Document related concepts
Rotating locomotion in living systems wikipedia , lookup
Natural selection wikipedia , lookup
Behavioral modernity wikipedia , lookup
Evolutionary mismatch wikipedia , lookup
Punctuated equilibrium wikipedia , lookup
Evolving digital ecological networks wikipedia , lookup
Theistic evolution wikipedia , lookup
Evidence of common descent wikipedia , lookup
Hologenome theory of evolution wikipedia , lookup
Transitional fossil wikipedia , lookup
Saltation (biology) wikipedia , lookup
Genetics and the Origin of Species wikipedia , lookup
Koinophilia wikipedia , lookup
Transcript
Changes in Living Things Over Time Changes Over Time • In order for a species to survive, in an ever changing environment, they must change as well – evolution. – As scientists study organisms from the past and compare them to organisms that currently live on the planet, they have discovered many evidences that organisms have gradually changed over time. • If a species does not change (adapt) it will ultimately die and the species will become extinct. Evidence of Evolution • Evidence that supports the theory of evolution : 1. 2. 3. 4. 5. Fossil Evidence Radioactive Dating Law of Superposition Anatomical Evidence Chemical Evidence 1. Fossil Evidence • Remains of a once living thing. • Bone, print, shelter, pollen, seeds – Not the complete organism but only the hard parts. 2. Radioactive Dating • Measures the age of a fossil through radioactive elements. – Decay rate of radioactive element = half life. • Half life = amount of time for half the element to decay. C14 half lives 1 half life = 5730 yrs 2 half lives = 11460 yrs 3 half lives = 17190 yrs 4 half lives = 22920 yrs 5 half lives = 28650 yrs www.ipj.gov.pl/ 3. Law of Superposition • Where an organism’s fossils can be found in the rock record. – Youngest on top • The most recent event to occur – Oldest on the bottom • The earliest event to occur www.sd41.k12.id.us/ 4. Anatomical Evidence • Jean-Baptiste de Lamarck (early 1800’s) – Concluded: living things had changed over time. – Homologous structures – body parts of different organisms with similar structures. • Human arm, bat wing, whale flipper and dog leg – Things did evolve thus becoming better adapted for their environment. www2.visalia.k12.ca.us/ Anatomical Evidence • Lamark’s downfall! – Believed that body structures change because of an inborn will to change and use. • Birds – had the desire to fly and over time thus developed wings • Giraffe neck- Started off short but with continual stretching it lengthened. – Eventually lost all credibility because of this. www.bellrevolution.com/ 6. Chemical Evidence • DNA is the basic unit of heredity. – More similar the DNA = more closely related the organisms. • Human vs. Human = 100% • Human vs. Chimpanzee = 98% • Human vs. Mouse = 92% • Protein molecule similarities can also determine common ancestors. – Scale of protein change = molecular clock • Who is the common ancestor to the Trachodon and Triceratops? Camptosaurus • Who is more closely related: – Trachodon and Stegosaurus – Apatosaurus and Triceratops – Thrannosaurus and Coelophysis – Coelophysis and Theodont Split most recently from each other Natural Selection • Charles Darwin – 1831, 5yr voyage on the Beagle • Studied plants and animals • Galapagos – noticed difference between island and mainland creatures. – Perfectly adapted to survive in a particular environment. – 1858 – Published On the Origin of Species • Stated his theory of evolution – natural selection www.charlesdarwinresearch.org/ Natural Selection • Natural Selection – survival and reproduction of those organisms best adapted to their surroundings. – 2 ways: 1. Overproduction - Producing more offspring than can survive. • • Competition for both food and shelter Those best adapted will survive and reproduce – survival of the fittest! – The fittest are selected by their surroundings Overpopulation Salmon eggs Tadpoles Dandelion Seeds Variation 2. Variation - No two members of a species are exactly alike. – Polar Bears – fur thickness • Survival of temperature variation is dictated by fur. – Peppered Moths – body colors • Pollution levels change bark colors – camouflage determines survival. Variation Polar Bear fur thickness Peppered Moths color Mouse color