Speciation Drives Evolution Unit 6: Evolution Ch. 16-3 Unit 6: Evolution Ch. 16-3.

Slides:



Advertisements
Similar presentations
Mechanisms of Speciation and Maintaining a Species.
Advertisements

Origin of Species Galapagos Tortoise.
THE ORIGIN OF SPECIES CHAPTER 24.
Examine how life continues to evolve within a changing environment
The Origin of Species If microevolution (the genetic changes within a population over generations) were all that ever happened, the Earth would only be.
SPECIATION. MICROEVOLUTION Microevolution is the change in allele frequencies within a population over a few generations Insects that carry the allele.
Ch. 24 – The Origin of Species
Speciation. What is Speciation? How does speciation occur? The formation of a species; when two or more species are created from an ancestral group Occurs.
1. Populations are geographically isolated
Copyright © 2009 Pearson Education, Inc. The origin of species is the source of biological diversity Speciation is the emergence of new species Every time.
SPECIATION -The Origin of Species. What is speciation?  Recap:  Species = a population or group of populations whose individual members can interbreed.
Copyright © 2009 Pearson Education, Inc. PowerPoint Lectures for Biology: Concepts & Connections, Sixth Edition Campbell, Reece, Taylor, Simon, and Dickey.
Copyright © 2009 Pearson Education, Inc.  A species can be defined as a group of organisms whose members can breed and produce fertile offspring, but.
LECTURE 8: Macroevolution. What is microevolution? –Evolution on a small scale –Change in allele frequencies from one generation to the next –A process.
Copyright © 2009 Pearson Education, Inc. PowerPoint Lectures for Biology: Concepts & Connections, Sixth Edition Campbell, Reece, Taylor, Simon, and Dickey.
Chapter 14 The Origin of Species Lecture by Joan Sharp.
How Diversity Evolves. Macroevolution The evolution of large scale diversity Evolutionary novelties Wings, feathers, brain sizes Speciation: origin of.
Species - a population(s) whose members have the potential to interbreed with one another in nature to produce fertile offspring, and cannot with members.
EVOLUTION Chapter 11.
What is Speciation? Speciation is the formation of new biological species, usually by the division of a single species into two or more genetically distinct.
Working with the Biological Species Concept Speciation is a two-part process –1. Identical populations must diverge –2. Reproductive isolation must evolve.
Speciation Speciation refers to the process by which new species are formed. Speciation occurs when gene flow has ceased between populations where it previously.
Objective: Speciation Do Now: Why is this population of horses considered to be the same species?
1 Origin of Species Chapter What you need to know! The difference between microevolution and macroevolution. The biological concept of species.
24 Speciation.
ORIGIN OF SPECIES CH 24. Speciation: origin of new species Microevolution: changes in allele frequencies Macroevolution: changes that result in formation.
INTRODUCTION TO EVOLUTION An Overview of Chapters 16 & 17.
Microevolution Microevolution: changes in allele frequencies and physical traits within a population and species So we know that alleles that allow cheetahs.
Speciation. Speciation is the origin of new species  A species is a population or group of populations whose members have the potential to interbreed.
Mom, Dad… There’s something you need to know… I’m a MAMMAL! The Origin of Species.
Evolution and Biodiversity
Macroevolution & Speciation
Macroevolution & Speciation
Please get out a piece of paper and a writing utensil.
Speciation.
Option D2: Species and Speciation
SPECIATION UNIT 5 EVOLUTION.
Where did all the species come from?
EVOLUTION and NATURAL SELECTION
Theory explaining how species form
Speciation Chapter 14 March 2014.
The origin of species is the source of biological diversity
Ch. 14 The Origin of Species
Speciation & Rates of Evolution
Do Now Explain the difference between directional and disruptive selection. Directional – one extreme of the variation of the trait is most fit Disruptive.
The Origin of Species.
How does a species evolve from preexisting species?
1.7: Speciation and extinction have occurred throughout the Earth’s history. 1. SPECIATION CONCEPTS.
Natural Selection What is natural selection? Natural selection is the way in which nature favours the reproductive success of some individuals within a.
Daily Warm-up February 25th What do you think defines a species
Finish questions & summary for 6-1 & 6-2 notes
Mechanisms of Evolutionary Change
Chapter 24 The Origin of Species.
How Populations Evolve
Why different species? Why are there 4,740 species of frogs in the world instead of 1 frog??
Population Genetics.
EVOLUTION and SPECIATION
Evolution and Zygotic Barriers
How do we create new species? How do old species become extinct?
Chapter 24 – The Origin of Species
Patterns of Evolution.
the formation of new species
Horse donkey Speciation mule.
Speciation -The definition of a new species is when it can NO LONGER REPRODUCE with the original population.
Making a species through evolution
SPECIATION pp
EVOLUTION & SPECIATION
Speciation and Time.
How does a species evolve from preexisting species?
Do now activity #5 What type of Natural Selection is selecting black rabbits? What type of Natural Selection is selecting for black AND white.
Presentation transcript:

Speciation Drives Evolution Unit 6: Evolution Ch Unit 6: Evolution Ch. 16-3

Speciation Speciation  Speciation  Speciation: changes that lead to the formation of a new species  Isolation often drives speciation  Species  Species are individuals who can successfully reproduce  Species share the same gene pool (alleles)  When 2 animals cannot mate, they are considered different species  Speciation  Speciation: changes that lead to the formation of a new species  Isolation often drives speciation  Species  Species are individuals who can successfully reproduce  Species share the same gene pool (alleles)  When 2 animals cannot mate, they are considered different species

Reproductive Barriers Reproductive Barriers  A. Pre-zygotic Barriers:  A. Pre-zygotic Barriers: isolating mechanism that prevent mating from happening at all (5 Types)

Geographic Isolation-  1. Geographic Isolation- population is separated by geographic barriers  Mountains, rivers, oceans, etc.  Ex: 2 squirrel species separated at the Grand Canyon Geographic Isolation-  1. Geographic Isolation- population is separated by geographic barriers  Mountains, rivers, oceans, etc.  Ex: 2 squirrel species separated at the Grand Canyon

Although they are in the same region, the white tailed antelope squirrel inhabits desert to the north of the canyon, while Harris’s antelope squirrel (above) has a more limited range to the south.

Habitat Isolation-  2. Habitat Isolation- Population uses different parts of the habitat  EX: One species of bird lives on the ground and the other lives in the trees Habitat Isolation-  2. Habitat Isolation- Population uses different parts of the habitat  EX: One species of bird lives on the ground and the other lives in the trees

Temporal Isolation-  3. Temporal Isolation- Individuals reproduce at different times  When some are ready to reproduce, others are not  EX: Squirrels reproducing at different times Temporal Isolation-  3. Temporal Isolation- Individuals reproduce at different times  When some are ready to reproduce, others are not  EX: Squirrels reproducing at different times

Mechanical Isolation-  4. Mechanical Isolation- individuals physically do not fit together to mate  anatomy does not correspond  EX: If a beetle’s reproductive organs (male & female) do not fit Mechanical Isolation-  4. Mechanical Isolation- individuals physically do not fit together to mate  anatomy does not correspond  EX: If a beetle’s reproductive organs (male & female) do not fit

Behavioral Isolation-  5. Behavioral Isolation- changes in courtship rituals cause indviduals not to breed  change in song or dance- they don’t recognize it so they don’t mate Grebes (birds) must dance together before they accept each other to mate  EX: Grebes (birds) must dance together before they accept each other to mate Behavioral Isolation-  5. Behavioral Isolation- changes in courtship rituals cause indviduals not to breed  change in song or dance- they don’t recognize it so they don’t mate Grebes (birds) must dance together before they accept each other to mate  EX: Grebes (birds) must dance together before they accept each other to mate

Let’s Dance!

Blue-footed boobies display their blue feet when courting potential mates.

Red-footed boobies are not impressed by the display.

Post-zygotic Barriers:  B. Post-zygotic Barriers: after reproduction occurs, this prevents a hybrid offspring from surviving or reproducing  EX: A mule (horse x donkey) is sterile, cannot produce offspring  EX: A liger (lion x tiger) never stops growing and will die Post-zygotic Barriers:  B. Post-zygotic Barriers: after reproduction occurs, this prevents a hybrid offspring from surviving or reproducing  EX: A mule (horse x donkey) is sterile, cannot produce offspring  EX: A liger (lion x tiger) never stops growing and will die

Types of Speciation Sympatric Speciation: same geographic area genetic changes  1. Sympatric Speciation: organisms live in same geographic area and speciation occurs due to genetic changes

Allopatric Speciation different areas geographic isolation  2. Allopatric Speciation: organisms live in different areas and speciation occurs due to geographic isolation

Speciation & Evolution Speciation & Evolution  Speciation drives evolution.  Microevolution  Microevolution is small changes in a species over time  DNA changes are used as evidence  Speciation drives evolution.  Microevolution  Microevolution is small changes in a species over time  DNA changes are used as evidence

 Macroevolution  Macroevolution is major changes in the history of live on Earth over millions of years  Due to microevolution over long period of time  Fossils are used as evidence  Macroevolution  Macroevolution is major changes in the history of live on Earth over millions of years  Due to microevolution over long period of time  Fossils are used as evidence

Mass Extinctions  Mass extinction is when a whole species goes extinct  Due to rapid, global environmental changes like ice ages, comet impacts, etc…  Mass extinction is when a whole species goes extinct  Due to rapid, global environmental changes like ice ages, comet impacts, etc…

 Adaptive radiation  Adaptive radiation: after a mass extinction there are many new niches open to be filled by survivors  EX: After dinosaurs went extinct, mammals evolved relatively quickly by using the new habitats and resources available and many new species arose  Adaptive radiation  Adaptive radiation: after a mass extinction there are many new niches open to be filled by survivors  EX: After dinosaurs went extinct, mammals evolved relatively quickly by using the new habitats and resources available and many new species arose