New User Special Price Expires in

Let's log you in.

Sign in with Facebook


Don't have a StudySoup account? Create one here!


Create a StudySoup account

Be part of our community, it's free to join!

Sign up with Facebook


Create your account
By creating an account you agree to StudySoup's terms and conditions and privacy policy

Already have a StudySoup account? Login here

BIO 102 Lecture (Ch. 24 The Origin of Species) Notes

by: Zach Notetaker

BIO 102 Lecture (Ch. 24 The Origin of Species) Notes BIO 102

Marketplace > University of South Carolina > BIO 102 > BIO 102 Lecture Ch 24 The Origin of Species Notes
Zach Notetaker

Preview These Notes for FREE

Get a free preview of these Notes, just enter your email below.

Unlock Preview
Unlock Preview

Preview these materials now for free

Why put in your email? Get access to more of this material and other relevant free materials for your school

View Preview

About this Document

These notes cover the content from Chapter 24 (The Origin of Species) of the textbook as well as the information presented during lecture.
General Biology
Mihaly Czako
Class Notes
25 ?




Popular in General Biology

Popular in Department

This 2 page Class Notes was uploaded by Zach Notetaker on Wednesday August 31, 2016. The Class Notes belongs to BIO 102 at University of South Carolina taught by Mihaly Czako in Fall 2016. Since its upload, it has received 51 views.


Reviews for BIO 102 Lecture (Ch. 24 The Origin of Species) Notes


Report this Material


What is Karma?


Karma is the currency of StudySoup.

You can buy or earn more Karma at anytime and redeem it for class notes, study guides, flashcards, and more!

Date Created: 08/31/16
BIOL 102 Lecture Notes 8/30/16 (Chapter 24) The Origin of Species  Speciation: origin of new species, focal point of evolutionary theory o Must explain how new species originate and how populations evolve  Microevolution: consists of changes in allele frequencies in population over time  Macroevolution: broad patterns of evolutionary change above species level, by same  mechanisms that cause microevolution  Species  Latin meaning “kind” or “appearance”  Biologists compare morphology, physiology, biochemistry, DNA sequences  Biological Species Concept: species = group of populations whose members can interbreed in  nature and produce viable, fertile offspring; DON’T breed successfully with members of other  populations o Gene flow b/w populations of same species holds a species together genetically      Limitations:  Can’t be applied to fossils or asexual organisms  Emphasizes absence of gene flow  BUT gene flow can occur b/w distinct species when some barrier is  broken naturally or artificially  Reproductive Isolation: existence of biological factors (barriers) impeding two species from  producing viable, fertile offspring  Hybrids: offspring of crosses b/w different species o Pre or post fertilization  Prezygotic barriers: block fertilization from occurring by… o Impeding different species attempting to mate o Preventing successful completion of mating o Hindering fertilization if mating successful  Postzygotic barriers: prevent hybrid zygote from developing into viable, fertile adult o Reduced hybrid viability o Reduced hybrid fertility o Hybrid breakdown  Morphological Species Concept: defines species by structural features o Applies sexual and asexual species but relies on subjective criteria  Ecological Species Concept: views a species in terms of its ecological niche o Applies sexual and asexual species and emphasizes role of disruptive selection  Phylogenetic Species Concept: defines species as smallest group of individuals on phylogenetic tree o Applies to sexual and asexual species but can be difficult to determine degree of  difference required for separate species  Allopatric (“Other Country”) Speciation: gene flow interrupted or reduced when population  divided into geographically isolated subpopulations  ex) flightless cormorant of Galapagos originated from fliying species on mainland o Definition of barrier depends on ability of population to disperse  ex) canyon can create barrier for small rodents, NOT birds, coyotes, or pollen o Separate populations can eveole independently thru mutation, natural selection, genetic  drift o Reproductive isolation can arise as by­product of genetic divergence  Increases as distance b/w species increases o Regions with lots of geographic barriers have typically have more species than do regions w/ fewer barriers  Physical separation alone isn’t biological barrier, reproductive barrier are intrinsic to organisms themselves  Sympatric (“Same Country”) Speciation: speciation takes place in geographically overlapping populations o Reproductive barrier isolates subset of population w/out geographic separation from  parent species o Can occur if gene flow is reduced by following factors:  Polyploidy: presence of extra sets of chromosomes due to accidents during cell  division  Much more common on plants than animals  Can produce new biological species in sympatry w/in single generation o Autopolyploid: individual with more than 2 sets of chromosome  sets (derived from single species) o Allopolyploid: species with multiple sets of chromosomes derived  from different species  Sexual Selection: can drive sympatric speciation  Habitat differentiation: appearance of new ecological niches  ex) North American maggot fly can live on native hawthorn trees & more  recently introduced apple trees


Buy Material

Are you sure you want to buy this material for

25 Karma

Buy Material

BOOM! Enjoy Your Free Notes!

We've added these Notes to your profile, click here to view them now.


You're already Subscribed!

Looks like you've already subscribed to StudySoup, you won't need to purchase another subscription to get this material. To access this material simply click 'View Full Document'

Why people love StudySoup

Steve Martinelli UC Los Angeles

"There's no way I would have passed my Organic Chemistry class this semester without the notes and study guides I got from StudySoup."

Jennifer McGill UCSF Med School

"Selling my MCAT study guides and notes has been a great source of side revenue while I'm in school. Some months I'm making over $500! Plus, it makes me happy knowing that I'm helping future med students with their MCAT."

Steve Martinelli UC Los Angeles

"There's no way I would have passed my Organic Chemistry class this semester without the notes and study guides I got from StudySoup."


"Their 'Elite Notetakers' are making over $1,200/month in sales by creating high quality content that helps their classmates in a time of need."

Become an Elite Notetaker and start selling your notes online!

Refund Policy


All subscriptions to StudySoup are paid in full at the time of subscribing. To change your credit card information or to cancel your subscription, go to "Edit Settings". All credit card information will be available there. If you should decide to cancel your subscription, it will continue to be valid until the next payment period, as all payments for the current period were made in advance. For special circumstances, please email


StudySoup has more than 1 million course-specific study resources to help students study smarter. If you’re having trouble finding what you’re looking for, our customer support team can help you find what you need! Feel free to contact them here:

Recurring Subscriptions: If you have canceled your recurring subscription on the day of renewal and have not downloaded any documents, you may request a refund by submitting an email to

Satisfaction Guarantee: If you’re not satisfied with your subscription, you can contact us for further help. Contact must be made within 3 business days of your subscription purchase and your refund request will be subject for review.

Please Note: Refunds can never be provided more than 30 days after the initial purchase date regardless of your activity on the site.