Name __________________________________________ Period _________ Date ________________ Chapter 16 -- Theory of Evolution Charles Darwin (1809-1882) ◦ English ___________________________ ◦ Took a trip around the world on a ship called _______________________________ ◦ Mostly fascinated with the ___________________________ Islands ◦ Best known for his theory of ______________________ by natural selection Darwin’s Journey ◦ Began in ____________ ◦ Sailed on a ship called the H.M.S. Beagle ◦ Five year voyage sailing around the coast of _____________________ ___________________________ and ___________________________ 1 Observations Aboard the Beagle ◦ Darwin collected 68 species of ___________________________ ◦ Wrote about the different characteristics of habitats and species that live there ◦ Species vary ___________________________ ◦ There are similar organisms around that world with similar ecological ___________________________ ◦ Ex: Rhea birds in S. America and ___________________________ in Africa ◦ Species vary ___________________________ ◦ Related animals species often occupy different habitats within a ___________________________ area ◦ Ex: Tortoise ___________________________ ___________________________ among Galapagos Islands ◦ Species vary ___________________________ ___________________________ ◦ Some fossils of ___________________________ animals were similar to living species ◦ Ex: Armadillo ___________________________ compared to modern day armadillos Darwin’s Findings ◦ Galapagos Islands ◦ Groups of animals _________________ from island to island ◦ Ex: tortoises and finches on the islands resemble each other but differ in the shape and function of their __________________ and _____________________ ◦ Believed these unique animals all came from a ______________________ ________________________ and they adapted to their environment 2 Evolution ◦ Development of new types of organisms _________________ __________________ ◦ Heritable _______________________ in the characteristics within a population from one generation to the next Ideas of Darwin’s Time ◦ Scientists thought all species were ___________________________ and unchanging ◦ The Earth was believed to only be a few ___________________________ (not billions) of years old ◦ During Darwin’s time, new research was being done to figure out the ___________________________ of the Earth ◦ James Hutton was a geologist in 1700’s ◦ Made connections between mountains, valleys, and layers of _______________ ◦ Believed the _________________ was older than thousands of years -a time so old for the human mind to image ◦ The Earth changes very _______________________ and some layers can accumulate as the environment is changing 3 ◦ Charles Lyell was a English ___________________________ that believed the Earth’s surface continues to change ◦ He explained that past processes that occurred are still occurring now ◦ Ex: ___________________________ erupted in the past and still today ◦ Published a great work called ___________________________ _______ ___________________________ in 1830 that built on the work of Hutton ◦ Darwin read this book while on his journey around the world ◦ Jean-Baptiste Lamarck ◦ French naturalist that ___________________________ the idea that populations of organisms change over time ◦ Proposed two hypotheses: Called Theory of ___________________________ ___________________________ ◦ Organisms could ______________________ during their lifetime by using or not using selected parts of the body ◦ Individuals could pass these ___________________________ traits on to their offspring ◦ Ex: Giraffes could ___________________________ their neck by stretching over a period of time to get the height they needed to eat and survive and then pass the longer neck trait to their ___________________________ 4 ◦ Thomas Malthus was an English economist in the 1790s ◦ Reasoned that if the human population grew continuously, there would not be enough ___________________________ for everyone ◦ His reasoning explained why plants and animals produced more a high amount of ___________________________ since a portion will not ___________________________ due to environmental factors ◦ Ex: Maple tree produces ___________________________ of seeds each summer ◦ Ex: Oysters produce ___________________________ of eggs each year with the understanding that only a fraction will survive Darwin’s Ideas ◦ Around the same time Darwin and Wallace formed ____________________ to explain evolution ◦ Darwin was able to publish his book first called _______ ________ __________________ ________ _____________________ in 1858 ◦ Book explained how evolution occurs by means of ___________________________ ___________________________ Artificial Selection ◦ Darwin studied ___________________________ breeders ◦ Farmers would select to breed only ___________________ with the largest fruit, or the ______________ that produce the most milk ◦ Darwin called this process ___________________________ ___________________________ 5 ◦ Nature provides the ___________________________ , and humans select hose they find to be useful and allow them to breed and pass on ___________________ to offspring Evolution by Natural Selection ◦ Mechanism from descent with ___________________________ ◦ 1. Struggle for Existence ◦ Organisms produce more offspring than can _________________________ ◦ Ex: dogs give birth to a ___________________ of puppies, but only a majority will survive ◦ 2. Variation and Adaptation ◦ Traits vary within a species and their environment called ___________________________ ◦ These adaptations help increase ______________________ to survive ◦ Ex: _______________________ with coral snake and scarlet snake ◦ 3. Survival of the Fittest ◦ Organisms best ___________________________ for an environment will survive best and ___________________________ ◦ The ability for an organism to ___________________________ and pass on adaptations ◦ 4. Natural Selection ◦ Process by which organisms with ___________________________ most suited to their local environment survive and leave more ___________________________ ◦ Organisms ___________________________ their mate based on desired traits 6 Common Descent ◦ Idea that every species must have ___________________________ by reproduction from pre-existing ____________________ that arrange over time ◦ Ex: finch _____________________ at Galapagos ◦ All species – living and extinct – are descended from ancient _____________ ancestors Transitional Species ◦ Organisms with features that are ___________________________ hypothesized ancestors Age of the Earth & Fossils ◦ Noted that fossils of extinct animals _________________________ living species ◦ Relative Age ◦ Age _________________________ to other fossils in order of old to young ◦ Absolute Age ◦ Using radioactive dating to get ________________ __________________ age ◦ Age of the Earth ◦ Geologists are certain based on evidence via radioactive dating to indicate the Earth is about _________ _______________________ years old ◦ Fossils ◦ ___________________________ of an organism that died long ago ◦ Many fossils form a series that can trace back to an ancient extinct ___________________________ ◦ Superposition ◦ Idea that ___________________________ form in layers where the layers closest to the _____________ are the younger than below 7 Anatomy and Embryology ◦ Anatomy: study of the ___________________ ◦ Embryology: study of ___________________________ ◦ Homologous structures ◦ Anatomical structures that originated from the ________________ common ___________________________ ◦ Ex: bones in arms of humans, penguins, alligator and bat ◦ Related _________________________ but _______________________ may differ ◦ Analogous Structures ◦ When structures have similar ___________________________ , but did not develop the same way ◦ Ex: wings of bat vs. bird ◦ Vestigial Structures ◦ Organs that no longer serve a ___________________________ in an organism ◦ Ex: human tail bone, appendix ◦ Embryology ◦ Similar patterns of embryological ___________________________ provide further evidence that organisms have descended from a ___________________________ ancestor ◦ Many animals look ___________________________ during development and produce ___________________________ tissue 8 Genetics and Molecular Biology ◦ At the molecular level, the ___________________________ ________________ and homologous molecules provide ___________________________ of common descent Phylogeny ◦ ___________________________ among groups of organisms ◦ Can make a “______________” of animals evolved ◦ Trunk of the tree would represent species that are ___________________________ related ◦ Branches represent a ___________________________ population or lineage 9 Evolution in Action ◦ Biologists tested the hypothesis by comparing ___________________________ from the various species ◦ DNA evidence supported hypothesis __________ that each lizard evolved ___________________________ on each island ◦ Convergent Evolution ◦ Process by which ___________________________ species evolve ___________________________ traits ◦ Ex: twig-dwelling species came from different ancestors but evolved similar adaptations to their environment Divergence & Radiation ◦ Divergence evolution ◦ Process by which the descendants of a ___________________________ ancestor diversify into species that each fit ___________________________ parts of the environment ◦ Ex: All breeds of dog share a common ancestor with wolves ◦ Adaptive Radiation ◦ Pattern of diversity when a new population in a new ___________________________ undergoes divergent evolution 10 Coevolution ◦ Evolution is on-going and many species may evolve ___________________________ Coevolution ◦ When __________________ or more species have evolved adaptations to each other’s ___________________________ ◦ Ex: ◦ Predator/Prey Interactions ◦ Introduction of new species ◦ Creating antibiotics 11