Bio 161 Ecology and Evolution Macroevolution Speciation.

Slides:

Advertisements

Similar presentations

Chapter 24 Species & Speciation.

Advertisements

Speciation How new species originate. Speciation (a.k.a macroevolution) There are two patterns of speciation as evidenced by the fossil record –Anagenesis.

Formation of Species A species is a population of organisms that can successfully interbreed but cannot breed with other groups. Existing species are changed.

The Origin of Species AP Biology Chapter 24.

1 The Origin of Species Chapter Outline The Nature of Species Pre and Postzygotic Isolating Mechanisms Geography of Speciation Hawaiian Drosophila.

Chapter 24 Notes The Origin of Species. There is more to evolution than just explaining how adaptations evolve in a population. Evolution must also explain.

Species and Their Formation

Species and Their Formation

Chapter 24: The Origin of Species

Ch. 24 – The Origin of Species

Copyright © 2009 Pearson Education, Inc. The origin of species is the source of biological diversity Speciation is the emergence of new species Every time.

The Formation of New Species. Isolation of Subpops  Mechanisms of evolution cause isolated subpops to diverge.

Outstanding Origin of Species Ch 24. Vocabulary  1. Macroevolution – origin of new taxonomic groups (new species, genera, families etc)  2. Speciation.

Chapter 24: The Origin of Species

Part 2 Evolution Notes. Natural Selection and Macroevolution Natural Selection shapes a population, making it adapted to its current environment. This.

Formation of Species Section 3.

Speciation Process by which a daughter species evolves from a parent species Genetic Divergence- when populations become reproductively isolated Species-population.

Evolution and Speciation. Species A group of organisms that breed with one another and produce fertile offspring.

Speciation Chapter 18.

Chapter 24 The Origin of Species. Question? u What is a species? u Comment - Evolution theory must also explain how species originate. u Darwin’s “Mystery.

Chapter 23 The Origin of Species. Question? u What is a species? u Comment - Evolution theory must also explain how species originate.

Origin of Species Chapter 24. Darwin Natural selection One species evolves due to adaptation to it’s environment Adaptation does not explain why one species.

Chapter 4 Evolution and Biodiversity. ORIGINS OF LIFE  1 billion years of chemical change to form the first cells, followed by about 3.7 billion years.

What is a Species? Speciation – the origin of new species The biological species concept defines a species as a population or group of populations whose.

The Origin of Species Chapter 24. Basic Patterns of Evolution Anagenesis  one species accumulates heritable changes, gradually the species becomes a.

Origin of Species Chapter 24. Darwin Natural selection One species evolves due to adaptation Adaptation does not explain why one species becomes another.

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 and Evolution

Module 1: Evolution MonthDayTopic Sept8Mechanisms of evolution I 11Mechanisms of evolution II 13Speciation 15Macroevolution 18Biodiversity 20The history.

Lecture Topic : Speciation I. Importance What are species? How do they evolve? II. Levels of Variation ~ microevolution A) Variation within locally breeding.

Biodiversity Studied in a relatively new field called Conservation Biology Consists of three components: 1.Species 2.Genes 3.Ecosystems.

David Sadava H. Craig Heller Gordon H. Orians William K. Purves David M. Hillis Biologia.blu B – Le basi molecolari della vita e dell’evoluzione The Origin.

Speciation How Species Form. Species How are new species defined? Used to be on basis of structure These are different species: –Top: Grevy’s zebra (endangered)

How Different Species Arise. What is a species? A group of organisms that can interbreed and produce fertile offspring in nature. New species arise through.

Mader: Biology 8 th Ed.. Population Genetics Genetic diversity in populations changes over generations Forces that cause populations to evolve Allele.

Species  “A species is a group of similar individual organisms that can usually breed among themselves to produce fertile offspring.” Ernst Mayr  Geneticists.

Chapter 14 : The Origin of Species Evolution is the source of biological diversity Most changes are minor.

Chapter 24: Speciation Objectives -Importance of reproductive isolation in the biological species concept -Speciation can take place with or without geographic.

What is a Species? Biological species = A population or group of populations whose members have the potential to interbreed with one another in nature.

THE ORIGIN OF SPECIES Chapter 24 Origin of Species Macroevolution – the origin of new taxonomic groups Speciation – the origin of new species.

24 Species and Their Formation. 24 What Are Species? How Do New Species Arise? Completing Speciation: Reproductive Isolating Mechanisms Hybrid Zones:

{ Evolution & Speciation Mechanisms & Models Quizlet:

Lesson # 8: Evolution (Speciation). Introductory Terms - In order for one population to become very different from another, they must be reproductively.

{ HOW BIOLOGICAL DIVERSITY EVOLVES Chapter 14. { THE ORIGIN OF SPECIES Chapter 14.1.

Ch.24 ~ The Origin of Species “That mystery of mysteries – the first appearance of new beings on this Earth.”

Speciation. What is a species? Biological species concept – a population or group of populations whose members have the potential to interbreed in nature.

{ Evolution & Speciation Mechanisms & Models.  Broad definition: species = one or more populations that share a trait derived from a common ancestor.

Chapter 24.  Evolution leads to potential speciation  One species becoming two or more species  Speciation leads to macroevolution  Broad changes.

Speciation Drives Evolution Unit 6: Evolution Ch Unit 6: Evolution Ch

What is a Species? Biological species = A population or group of populations whose members have the potential to interbreed with one another in nature.

8.2 Speciation Pages

Speciation & Macroevolution

Speciation & Rates of Evolution

The Origin of Species.

Evolution OF NEW SPECIES

Chapter 16: The Origin of Species.

10.3 Gene pools and speciation

The process of evolution drives the diversity and unity of life

Random Change Changes in a gene pool can be caused by a number of different factors: Small populations are prone to changes in gene frequency from chance.

Chapter 22 Bozeman Tutorial: Speciation (11:39)

The Origin of Species Chapter 24.

Chapter 24 Notes The Origin of Species.

Speciation: The Origin of New Species

Population Genetics Population: a group of organisms of the same species living together in a given region and interbreeding. Allele: Different forms of.

1.C.1: Speciation and Extinction

Presentation transcript:

Bio 161 Ecology and Evolution Macroevolution Speciation

Species = Groups of actually (or potentially) interbreeding natural populations that are reproductively isolated from other such groups. Ernst Mayer. Population genetic translation: a single gene pool. ? Morphological or Genetic Species

Bufo woodhousie (Fowlers toad) streams Bufo americanus (American toad) Rain puddles

Progomphus obscurus: rivers and streams Progomphus alachuenis: lakes

Quesrcus lobata California valey oak Moist mountain slopes Quercus dumosa Shrub oak Dry chaparral

Rana sylvaticus (Wood frog) Rana pipiens (Leopard frog)

Lactuca graminifolia: Flowers in early Spring Lactuca canadensis: Flowers in Summer Two species of wild lettuce growing together along roadsides throughout southeastern US.

Salvia melliferaSalvia apiana

HorseMuleDonkey

Zebrass

Colonization and founder effect. Barriers to movement Extinction of intermediate populations

Allopatric speciation of pupfishes (Cyprinodon) in Nevada desert pools.

Desert Pupfish. These fish are about the size of guppies and live in various small pools in this part of Nevada and California. Each pool has its very own distinct species of Pup Fish and all are endangered.

Distribution of Pupfish

Allopatric speciation of Hawaiian goose (the Nene)

Pollinator switching in species with highly specialized pollination mechanism may also lead to sympatric speciation. The two orchids above are very similar and have completely overlapping ranges, yet are pollinated by different species of solitary bees. In this genus, pollinators are attracted by the flowers' species- specific chemical attractants that mimic the female pheromones of the targeted insects. Left, Yellow-bee Orchid (Oprys lutea), right, Ophrys sicula. The latter species was regarded as a variant of the former for long.

HorseMuleDonkey

2n = 18 2n = 36

Galeopsis pubescens (2n = 16) Galeopsis speciosa (2n = 16)

(2n = 32) Hemp nettle (G. pubescens x G. speciosa)

Sympatric speciation and allopolyploidy in wheat.

Sympatric speciation with alloploidy of Gilia species. A hybrid zygote Gilia major (n=18) resulted from a cross between G. aliquanta (n=9) and G. minor (n=9) followed by genome duplication.

Fig

Rapid speciation because of: 1.Adaptation to a new environment 2.Genetic drift 3.Character displacement: a)Resource partitioning b)Building pre-zygotic isolation mechanisms.

Fig

Fig

Convergent Evolution

Ordovician Devonian Permian Triassic Cretaceous

Siberian Traps

Volcanic eruption  CO 2 increase in the atmosphere  Global warming  Loss of O 2 of the ocean  Growth of sulfate reducing bacteria  H 2 S production  Killing of marine animals  Release of H 2 S in the atmosphere  Killing of terrestrial life.

The End.