1. Warm-Up (2/11)
On the piece of white paper from the back, answer the following question.
Name
Date
Period
You read about fruit flies having red (w+) or white (w--) eyes in last week’s CTQ’s. Flies without red pigment have a mutation in the white gene (w--); flies with the red pigment are considered wild-type (w+). Explain how the allele frequency should change over the course of five generations of a population with an equal distribution of red- and white-eyed flies, if w+ allele has a selective advantage.

2. 2D.3b: Disruptions to ecosystems impact the dynamic homeostasis or balance of the ecosystem.
Illustrative example: natural disasters
1C.1a: Speciation rates can vary, especially when adaptive radiation occurs when new habitats become available.
1C.1b: Species extinction rates are rapid at times of ecological stress.
Illustrative example: Five major extinctions
1C.2a: Speciation results in diversity of life forms. Species can be physically separated by a geographic barrier such as an ocean or a mountain range, or various pre- and post-zygotic mechanisms can maintain reproductive isolation and prevent gene flow.
1C.2b: New species arise from reproductive isolation over time, which can involve scales of hundreds of thousands or even millions of years, or speciation can occur rapidly through mechanisms such as polyploidy in plants.

3. Speciation (1) Physically isolated.
Speciation occurs when two groups become reproductively isolated from each other.
Romeo!
Juliet!

4. Speciation (1) Physically isolated.
Speciation occurs when two groups become reproductively isolated from each other.

5. Speciation (1) Physically isolated.
Speciation occurs when two groups become reproductively isolated from each other.
(2) “Pre-zygotically” isolated (cannot/will not mate)
Eww… feathers!
Eww… bald!

6. Speciation (1) Physically isolated.
Speciation occurs when two groups become reproductively isolated from each other.
(2) “Pre-zygotically” isolated (cannot/will not mate)
¡ay caramba!

7. Speciation (1) Physically isolated.
Speciation occurs when two groups become reproductively isolated from each other.
(2) “Pre-zygotically” isolated (cannot/will not mate)
(3) “Post-zygotically” isolated (offspring dead or sterile)

8. Chromosomes don’t match up!
Speciation
(1) Physically isolated.
Speciation occurs when two groups become reproductively isolated from each other.
(2) “Pre-zygotically” isolated (cannot/will not mate)
(3) “Post-zygotically” isolated (offspring dead or sterile)
Chromosomes don’t match up!

9. Speciation Generation 1 Generation 2
Speciation can happen quickly (like in plants)…
Generation 1
No genetic change
Whole-genome duplication
Generation 2

10. Speciation Let’s start eating fruits more!
Speciation can happen quickly (like in plants)…
…or slowly (like when groups find a new environment).
Let’s start eating fish more!

11. Critical Thinking Question #1
A population of tree monkeys is only found in a remote forest of Ecuador. In 2005, a drought led to massive forest fires, greatly diminishing the tree monkey population.
Describe how speciation could occur in the tree monkey population in the context of genetic drift following the forest fire. (LO 1.24) (LO 2.28)

12. 2D.3b: Disruptions to ecosystems impact the dynamic homeostasis or balance of the ecosystem.
Illustrative example: natural disasters
1C.1a: Speciation rates can vary, especially when adaptive radiation occurs when new habitats become available.
1C.1b: Species extinction rates are rapid at times of ecological stress.
Illustrative example: Five major extinctions
1C.2a: Speciation results in diversity of life forms. Species can be physically separated by a geographic barrier such as an ocean or a mountain range, or various pre- and post-zygotic mechanisms can maintain reproductive isolation and prevent gene flow.
1C.2b: New species arise from reproductive isolation over time, which can involve scales of hundreds of thousands or even millions of years, or speciation can occur rapidly through mechanisms such as polyploidy in plants.

13. Extinction Fleenzauts Fleenzarks
Extinction is the elimination of a species…
…caused by destabilization of an ecosystem.
Fleenzauts
Fleenzarks

14. Extinction
Scientists have declared Earth is currently experiencing a sixth mass extinction.
There have been five major mass extinctions caused by massive climate change.
Extinctions have occurred at over 1,000 times the background extinction rate since 1900.*
*Malcom et al, 2015

15. Critical Thinking Question #2
201.3 Million years ago (Ma), most marine and terrestrial species became extinct in what is known as the Triassic-Jurassic era. Other species, such as crocodylomorphs, were greatly reduced in population size and genetic variation. Explain how the aftermath of this extinction event might have led to new speciation events.

16. Closure
On the piece of white paper from the back, answer the following question:
Name
Date
Period
State three situations in which a population could separate into two species.
Scale 1 – 10