biology unit 7 evolution evidence for evolution notes
TRANSCRIPT
Unit 7: Evidence
for Evolution
(1) Beginning Ideas…
• Living things adapt to their environment to survive.
• All living things have similarities to one another.
• Living things rely on resources to survive.
• The traits living things have, allow them to survive during times of famine/disease/change.
• The earth has changed several times over millions of years.
(2) Darwin
• Biologist during the 1800’s.
• He noticed that:– Organisms have unique body structures,
adapted to their living environment.– Different types of organisms still function
similarly, and/or have similar body parts.– Populations are very diverse. Some animals are
better suited to survive than others.
(3) Lamarck
• Biologist/Naturalist during 1800’s (along with Darwin).
• He thought that:– Animals just magically grew body parts to adapt
to their environment.– That when animals make changes to
themselves, they can pass on those changes to their offspring.
– He was WRONG!!
(4) Types of Evidence…
• Fossil Records
• Comparative Anatomy
• Biogeography
• Carbon dating and chemical composition
• Embryology
• DNA / Genetics
(5) Comparative Anatomy
• By looking at fossils scientists can:– Identify species which are extinct.– Understand how and when certain anatomical
features developed, and in which types of environments.
• Scientists can look at the skeletal structure of different types of animals and…– Look at similarities in body part development,
position and structure.– Look at differences and consider causes.
(6) Types of Body Structures
• Homologous Structures Features in the body part that are similar between different types of animals, because they all evolved over time from one common ancestor.
• Analogous Structures Features in the body part that are similar between different types of animals, because they evolved in similar environments.
• Vestigial Structures Features in the body part, found between different animals, but no longer have functions. (Proving a connection to a common ancestor.)
