Unit 11 Evolution Unit 11 Quiz 21916 Unit

Unit 11: Evolution Unit 11 Quiz: 2/19/16 Unit 11 Test: 2/23/16

History of the Earth How old is the earth?

• The earth is approximately 4. 6 Billion years old • Scientists believe that life originated in the oceans between 3. 9 & 3. 4 billion years ago. • How do we know that?

• Paleontologists – are scientists who study ancient life • They study Fossils- Evidence of an organism that lived long ago

Evidence of Evolution A. Evidence from Fossils 1. Types: Imprints, molds (impressions), casts (filled impression), tracks, hard parts, actual remains. 2. Dating Fossils a) Absolute Dating 1) Radioactive isotopes- C-14 dating b) Relative Dating 1) Sediments are layed down in strata 2) Lowest layers are oldest 3) A fossil's position in undisturbed rock gives its age relative to other fossils.

Make a time line of earth’s history: 1. Turn to page 374 -375 2. Using a meter stick construct a time line of earth’s history 3. 1 meter = 1 billion years 4. 1 centimeter = 10 million years 5. 1 millimeter = 1 million years 6. Follow the instructions and construct your timeline

UNIT XI – EVOLUTION Test Friday 2 -24 THEORY OF EVOLUTION The theory of evolution is one of the most fundamental concepts in Biology. Evolution Is defined as _____ in a changes _________over time. The population of organisms scientist considered to be the founder of modern evolutionary theory is _______. Charles Darwin

A. History of Evolutionary Theory During the 1700 s, several scientists began challenging the idea of a world in which changes did not occur. These scientists and their hypotheses were very important to Darwin’s work.

A. History of Evolutionary Theory Geologists (Hutton & Lyell) first 1. Gradualism - _________ older suggested that the planet was much ______ than previously thought; began to find changes were slowly, but evidence that _______ constantly taking place.

A. History of Evolutionary Theory 2. Malthus – Published an essay that had a huge impact on Darwin. Proposed that organisms over ____ - reproduce; in other words, reproduce at a _____ greater rate than resources can supply

A. History of Evolutionary Theory 3. Lamarck was one of the first scientists to propose changes in a mechanism for evolution; that is, the _______ population time a _____ of organisms over _____. His major hypotheses included:

3. Lamarck Cont. Tendency Toward Perfection – Stated that organisms were continually changing in more successfully order to live ________.

3. Lamarck Cont. Use and Disuse – Changes in size ____ and/or ______ shape of a structure in an organism was a response to use or disuse. grew bigger Structures used extensively ____ and structures used less frequently got smaller _____. Acquired Traits Inheritance of ____

Acquired Traits

B. Charles Darwin (1809 – 1882) 1. Darwin’s History Darwin’s data was collected on a 5 -year journey around the world on the USS Beagle ______. He made observations and collected data throughout the journey. He used this data to propose a hypothesis ____ to explain the diversity he saw.

1. Darwin’s History Cont. The area that had the greatest impact on Galapagos Islands due Darwin was the _____ to the differences he saw in the same animals living on different islands.

Galapagos

• He began to suspect that populations from the mainland changed after reaching the Galapagos.

• Upon his return he talked to animal breeders & called what they did to direct breeding to produce offspring with the Artificial selection desired traits _________, same as what we called selective breeding last unit.

2. Darwin’s Observations • Members of a population often vary greatly in traits their _____. parents to offspring • Traits are inherited from _________. more • All species are capable of producing _____ offspring than environment ___________ can support • Variations that increase reproductive success will have greater change of being passed on than those that do not increase repro. success

3. Darwin’s Theories Based on his observations and the hypotheses of other scientists: traits tend to • Organisms with favorable ____ reproduce thereby leaving survive and _____; more descendents than other individuals • This will result in an accumulation of these offspring changing the traits in the ____, genetic original _______make-up of the population

4. Darwin’s Legacy • Did not publish his findings for years • Alfred Wallace – formed identical hypotheses ______ based on his research. Sent his manuscript to Darwin, and finally Darwin was persuaded to publish his own conclusions Origin of Species • Released “_______”, still considered one of the greatest scientific studies ever

III. THE PRINCIPLES OF EVOLUTIONARY THEORY A. Evolution occurs because of natural selection - a mechanism for change that occurs when organisms with favorable _____ characteristics for a particular environment ______, reproduce ____, and pass these survive offspring characteristics on to ____.

III. THE PRINCIPLES OF EVOLUTIONARY THEORY B. The ability of an organism to survive and reproduce in its environment is fitness known as ________.

III. THE PRINCIPLES OF EVOLUTIONARY THEORY C. Fitness is based on _______. adaptations An adaptation is any trait that aids in the survival reproduction of an organism. _______ and ______ on a cactus, Examples of adaptations are thorns ________________________ camouflage , antibiotic resistance in bacteria

III. THE PRINCIPLES OF EVOLUTIONARY THEORY D. As organisms ____ survive and adapt, speciation may occur. Speciation is _____ the formation of new species - a group of breed similar organisms that _______ with one fertile offspring…. another and produce ______ that is, babies that can make babies ______________.

• For speciation to occur population must diverge & then be reproductively isolated. • Two types of speciation: – Allopatric speciation: physical barrier divides population into two or more: Abert & Kaibab squirrels of the Grand Canyon • Ex. __________________

• Sympatric speciation: species evolves into new one without a physical barrier. Seen in insects & plant species

F. Isolating Mechanisms: allow for the gene separate pools to become ______ so they can form a new _____. species Reproductive isolation- as new ______ species evolves, populations become reproductively _________ isolated from each other.

• Prezygotic- prevents reproductions by making fertilization unlikely ___________ because of geographic, ecological, behavioral, temporal or other differences. & Western Meadowlark • Ex: Eastern _____________ have overlapping ranges & are similar in appearance but use different mating songs & do not interbreed. • Ex: Fireflies- similar species but mate at different ___________ times of night

• Postzygotic- when fertilization has hybrid occurred but a ______ offspring Cannot develop _________or reproduce; prevents offspring survival or reproduction • Ex. Mule, liger

III. THE PRINCIPLES OF EVOLUTIONARY THEORY G. The failure of an adapt organism to _____ to changes in its environment will ultimately lead to its _____ extinction because of natural selection ________.

III. EVIDENCE FOR EVOLUTION A. Fossils – Fossils are preserved bones and traces of organisms ___________________ Fossils provide a record of earlier life and evidence that evolution has occurred. Fossils also provide evidence about the earth’s climate life forms. _______ geography, & ______ 90%of Earth’s history occurred during the Almost ____ Precambrian ________ Time.

Copyright Pearson Prentice Hall

III. EVIDENCE FOR EVOLUTION • There are two major classes of traits when studying transitional fossils: derived traitsnewly evolved features such as feathers, that do not appear in the fossils of common ancestors & Ancestral traitsmore primitive features such as teeth & tails, that do appear in ancestral ones

III. EVIDENCE FOR EVOLUTION B. Biogeography- Variations are seen in the same types of animals based on their environment _______. In addition, there are some organisms that live in very different locations but they have similar characteristics because __________________ Their envirnoments are similar: ex. Climate, food sources, ect.

III. EVIDENCE FOR EVOLUTION C. Comparative anatomy– Scientists use anatomical studies of different organisms for evidence of evolutionary relationships. 1. Homologous structures-For example, similar appendages that are very ______ in structure, but differ in ______ are known as function homologous structures. Examples of ______ homologous structures are arm of human, flipper of dolphin, wing of bat ___________________.

III. EVIDENCE FOR EVOLUTION 2. Vestigial Structures - A structure that is reduced _____ in function in a living organism, but may have been used by an ancestor is known as a vestigial structure. A structure may become _______ vestigial when an organism changes in form or behavior. Examples are wings _______ of ostrich eyes on cave fish, human appendix ________________.

III. EVIDENCE FOR EVOLUTION 3. Analogous structures- Not all similar features are evidence of common ancestry. Analogous structures ca be same purpose used for the _______ & can be superficially similar in construction but are not inherited _______ from a common ancestor. They show that functionally similar features can evolve independently in similar environments. Ex wings birds vs. insects

III. EVIDENCE FOR EVOLUTION D. Embryology – Similarities in the structures of developing ____ embryo of different organisms are considered to be proof of a close evolutionary relationship.

III. EVIDENCE FOR EVOLUTION E. Comparative biochemistry– Scientists use DNA studies to determine the evolutionary relationship between organisms. The more similar the DNA, the closer the evolutionary relationship ________________

IV. MECHANSIMS FOR EVOLUTION Evolution does not occur in an individual; instead it refers to heritable changes that occur in a ________ over time. There must be population genetic mechanisms available for ____ changes to occur:

V. MECHANSIMS FOR EVOLUTION Cont. A. Mutation – A mutation is a change in DNA _______. Although mutations harmful sometimes are most often _______, the resulting change in _____ phenotype may be beneficial to an organism under certain conditions. In jaguars, the mutation is dominant hence black jaguars can produce both black and spotted cubs, but spotted jaguars only produce spotted cubs when bred together.

V. MECHANSIMS FOR EVOLUTION Cont. gametes If the change occurs in the ____, this change will be passed onto the offspring of that organism. A positive mutation that provides a survival advantage is known as an adaptation _____.

V. MECHANSIMS FOR EVOLUTION Cont. B. Diploidy – Most organisms are diploid, which means double set of chromosomes ____________. This allows for increased genetic variation in a population. Heterozygote Advantage – Seen in sickle cell allele malaria ________ and _____. Recombination – Leads to increased genetic variation as a result of crossing over prophase I _______ during _____ of _______. meiosis

V. MECHANSIMS FOR EVOLUTION Cont. C. Gene Flow – Gene flow occurs when organisms from one community migrate to alleles another. This introduces new _____ population which can lead to a into the _____ change in the genetic make-up of the population.

V. MECHANSIMS FOR EVOLUTION Cont. D. Genetic Drift – This describes a situation in which change in a population is magnified because the population size is very ______. small Causes of genetic drift include

V. MECHANSIMS FOR EVOLUTION Cont. Bottleneck effect – large portion of population ___________ destroyed in disaster Founder effect – segment of population moves to new ____ habitat Simple illustration of founder effect. The original population is on the left with three possible founder populations on the right

IX. MECHANSIMS FOR EVOLUTION Cont. • E. Single Gene Traits-Natural selection single gene traits can lead to changes on _____ in ______ allele frequencies and therefore to evolution. EX. ___________ Color change in a lizard poplution

IX. MECHANSIMS FOR EVOLUTION Cont. F. Polygenic Traits-Natural selection can affect the distributions of phenotypes in 3 ways: one • Directional Selection-Individuals at ___ end of the bell curve have higher fitness than those in the middle or other end. Birds with bigger beaks are selected for over EX: ________________ Medium & small beaks. _________________

IX. MECHANSIMS FOR EVOLUTION Cont. middle • Stabilizing Selection-Individuals in the ____ have the highest fitness causing the curve to narrow. Birth weight, babies in the middle weight range are more • EX: _____________________________________ likely to survive than smaller or larger babies • Disruptive Selection-when individuals at the ends of the curve have the higher fitness. If lasts long enough can ends distinct cause the curve to split in two and create _____ phenotypes. EX. Finches beak sizes, large & small beaks are selected for &the medium beak _______________ Struggle to survive.

IX. MECHANSIMS FOR EVOLUTION Cont.

V. MACROEVOLUTION • A. Extinction-More than ____% of all 99 species that have ever lived are now ______, extinct which means the species has died out. Darwin proposed possible reasons with competition for ______________ resources & environmental change

Fig. 1: Number of assessed taxa in each species group in Volume 1. For each species group, the pie chart shows the absolute number of taxa and that number as a percentage of all taxa (n = 478). By agreement, neobiota are not included in the analysis.

V. MACROEVOLUTION Mass extinction has occurred several times, • ______ wiping out entire _____. ecosystems Meteorites , volcanic action, and ______ Tectonic plate • _______ movement has been blamed. evolution • Mass extinctions clear the way for _____ Mammals of other species. EX: _____

V. MACROEVOLUTION B. Adaptive radiation or divergent evolution single species has evolved the process where a _____ natural selection into diverse forms that through ________ live in short period of time that live in different ways. Often follows mass extinctions EX: Finches & tortoises of the Galapagos _____________ evolution C. Convergent ___________ when unrelated species evolve similar traits even though they live in different parts of the world because of similar ecology & climate. EX: _________ Mara of South America & rabbit of England

X. MACROEVOLUTION Co-evolution is when a change in one organism D. _______ corresponding change in another organism. leads to a ______ EX: ________ Orchid/bee/moth E. __________ Punctuated Equilibrium is another pattern gradualism punctuated equilibrium is of evolution. Unlike _____ characterized with long periods of _____ interrupted stability by brief periods of ______ rapid change. It is controversial but known that evolution does occur at different rates.