Class Notes (921,843)
CA (542,678)
UTSC (32,886)
BIOA02H3 (533)
Lecture

Speciation

2 Pages
115 Views

Department
Biological Sciences
Course Code
BIOA02H3
Professor
Dr.Persaud

This preview shows half of the first page. Sign up to view the full 2 pages of the document.
Speciation
Mechanisms of reproductive incompatibility fall into 2 categories:
1. PREZYGOTIC Reproductive Barriers
Operate before fertilization occurs
(a) Habitat Isolation
-Therefore never come into contact
(b) Temporal Isolation
-Mating periods do not overlap.
(c) Mechanical Isolation
-Differences in size and shape of reproductive organs.
E.g. Duck genitalia: male penis & female reproductive tract
(d) Gametic Isolation
-Eggs dont have appropriate chemical signals for sperm of another species
-Or sperm is not able to attach to and penetrate the egg.
(e) Behavioural Isolation
-Individuals reject or fail to recognize potential mating partners.
e.g. courtship rituals
2. POSTZYGOTIC Reproductive Barriers:
-Survival and reproduction of hybrid offspring are reduced.
(a) Low Hybrid ZYGOTE Viability
- Fail to mature or have severe abnormalities.
(b) Low Hybrid ADULT Viability
- Survival rate of hybrids is less than that of normal offspring
(c) Hybrid Infertility
E.g. mules
Reinforcement- the strengthening of prezygotic barriers
www.notesolution.com

Loved by over 2.2 million students

Over 90% improved by at least one letter grade.

Leah — University of Toronto

OneClass has been such a huge help in my studies at UofT especially since I am a transfer student. OneClass is the study buddy I never had before and definitely gives me the extra push to get from a B to an A!

Leah — University of Toronto
Saarim — University of Michigan

Balancing social life With academics can be difficult, that is why I'm so glad that OneClass is out there where I can find the top notes for all of my classes. Now I can be the all-star student I want to be.

Saarim — University of Michigan
Jenna — University of Wisconsin

As a college student living on a college budget, I love how easy it is to earn gift cards just by submitting my notes.

Jenna — University of Wisconsin
Anne — University of California

OneClass has allowed me to catch up with my most difficult course! #lifesaver

Anne — University of California
Description
Speciation Mechanisms of reproductive incompatibility fall into 2 categories: 1. PREZYGOTIC Reproductive Barriers Operate before fertilization occurs (a) Habitat Isolation -Therefore never come into contact (b) Temporal Isolation -Mating periods do not overlap. (c) Mechanical Isolation -Differences in size and shape of reproductive organs. E.g. Duck genitalia: male penis & female reproductive tract (d) Gametic Isolation -Eggs dont have appropriate chemical signals for sperm of another species -Or sperm is not able to atta
More Less
Unlock Document


Only half of the first page are available for preview. Some parts have been intentionally blurred.

Unlock Document
You're Reading a Preview

Unlock to view full version

Unlock Document

Log In


OR

Don't have an account?

Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


OR

By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.


Submit