1. 7A – Evidence of Evolution
Fossil Evidence & Biogeography
7A analyze and evaluate how evidence of common ancestry among groups is provided by the fossil record, biogeography, and homologies, including anatomical, molecular, and developmental.

2. 5 min
In:
How does fossil evidence gives us clues to how organisms from the past are related to organisms from today?
Write your answer on the paper
Discuss with partner
Discuss as a class
Collect student answers and discuss

3. Dating the Fossil Record
3 min
Dating the Fossil Record
You have received nine rock samples from a paleontologist in California.
Your job is to arrange the samples in order from oldest to youngest according to their fossil content .
Results from absolute dating methods will not be available from a laboratory for several weeks, and the paleontologist needs the information immediately.
Begin with Sample 2. They are the oldest rocks.
You have 3 minutes!!!!

4. 2 min
2, 1, 5, 7, 9, 3, 4, 8, 6

5. Dating the Fossil Record
2 min
Dating the Fossil Record
Discuss with your partner or group
Describe what might have happened to some of the organisms from the beginning to now.
Develop a hypothesis of how some of the species changed or became extinct over time?
Do you have any evidence?

6. Dating the Fossil Record
2 min
Dating the Fossil Record
Discuss with your partner or group
Which one of the species is the common ancestor? Which sample can we find it in?
Which one of the species is the modern species? Which sample can we find it in?
Does the modern species resemble the ancient common ancestor?

7. Evolution is a Theory – Just like Gravity!
Evolution - gradual change in the genetic makeup of a population through successive generations .
Theory - a well tested explanation supported by evidence

8. Description
Similarities of __________ in the fossil record reflects that organisms have a common ancestor.
_______________ in bone structure of specific species shows _____________ over time.
Fossil record has revealed links between large groups of organisms such as from _________ to __________ and reptile to __________.
change
fish
reptile
species
bird
variations

9. Fossil Record shows: complex arise gaps gradual
Relative ____________ of a species
How species found in the ________________ layers are very ___________ from what is in the top layer
Species today are more ______________ (cell structure, DNA)
That when new species _____________, others become ____________
_________________ evolution in species over time
_________ in the timeline and is not __________.
age
different
complete
extinct
bottom

12. Evolution of the Horse

13. Biogeography

14. Biogeography Simulation
See lesson plan for directions

15. In:
Why are some species only found in some parts of the world and not others?
Write your answer
Discuss with partner
Discuss as a class 

16. Description: Biogeography
the study of _________________________ isolation and _____________________ drift.
geographical
continental

17. Species
a group of individuals that actually or potentially interbreed (sexually) in nature
For example, these happy face spiders look different, but since they can interbreed, they are considered the same species: Theridion grallator.

18. Speciation event that produces two or more separate species
Click here for the story

19. How does one species become two species?
Reproductive isolation is the most common cause.
For example, if some flies land on an island with no flies they may evolve into one or more new species that are different from the species where they originally came from.

20. Diversity Name some animals that inhabit the austin-round rock area.
Aka: biodiversity
the different varieties of organisms inhabiting a particular region

21. Geographical Isolation
Describe what you think this might mean to your partner.
Species are separated due to an event or natural barrier – leads to speciation

22. Biogeography
(clockwise from top) a chameleon, an aye aye, a fossa, and a baobab. All are native to Madagascar.
Why is Madagascar home to so many unique plants and animals?
Why is Madagascar home to so many unique plants and animals? Because the island's geography, geology, and climate have provided opportunities for species to evolve and diversify in isolation. Its species are a mix of those that have been living and evolving there for many tens of millions of years and those that arrived more recently and subsequently diversified.

23. Madagascar then….
Understanding where all of Madagascar's species came from (i.e., its biogeography) requires understanding Madagascar's own geologic history. One hundred and seventy million years ago, Madagascar was landlocked in the middle of the supercontinent Gondwana, sandwiched between land that would eventually become South America and Africa and land that would eventually become India, Australia, and Antarctica.

24. Madagascar then & now…
Through movements of the Earth's crust, Madagascar, along with India, first split from Africa and South America and then from Australia and Antarctica, and started heading north. India eventually smashed into Asia — forming the Himalayas in the process — but Madagascar broke away from India and was marooned in the Indian Ocean. Madagascar has been on its own for the past 88 million years.

25. Madagascar…..now! Rarest species on earth found no where else
Some of Madagascar's present species are there because they "rode there" on the continents and were left on the island when it separated from India. Others arrived on the island after its split, immigrating from other places.

26. Speciation: From 1 specie to 5.
One simple specie
Island breaks away – species A evolves into species B
Island breaks away again – species B evolves into species C
Geographic isolation occurs because of mountain ranges – species C is separated leading to a new species D
Island breaks away again – species D evolves into species E.

27. From 1 specie to 5. Who is the ancestral species?
Is the ancestral species still alive today? How?
Are these species related to each other?
What’s another way new species can show up in an isolated area?
Ancestral species = A
Alive today because it lived in isolation with no other changes occurring

28. The following mammals did not exist in Madagascar but instead they used natural rafts to get to the island. (At least in theory)

29. So if you had ticket, you had a ride
Why don’t lions, elephants, apes, antelopes, & zebras exist in Madagascar?
Madagascar has an unusual mix of wildlife. For example, the island does not have apes, monkeys, elephants, zebras, giraffes, lions, hyenas, rhinos, antelopes, buffalo, or camels that you might expect to find in Africa, but it does have lemurs, tenrecs, boa constrictors, iguanas, and other creatures.
Most of these animals are very large and had no way of making it across the water to Madagascar.

30. Any animal can move to another location as long as it can find a way.

31. Out:
Describe how evidence of common ancestry is provided by biogeography. Use the terms: common ancestor, species, speciation, diversity, geographic isolation, continental drift.

32. Predict: From what you have learned about the fossil record and biogeography, predict what happened to the Hawaiian Islands and to the number of species over time.
Due to extreme geographic isolation, no land mammals ever reached Hawaii prior to the arrival of people. There were thousands of plant and animal species in Hawaii that existed nowhere else on our planet. The same was true of New Zealand.

33. At which node is the common ancestor of chimps and orangutans?
To which primate are humans most closely related? How do you know?
At which node is the common ancestor of all primates? How many years ago did it exist?
Is it accurate to say that humans came from chimps? Explain.
Gibbon
Orangutan
Chimp
Human
Gorilla
15 MYA
5 MYA
10 MYA
Today A D C B
MYA= Millions of years ago
Above image modified from
Based on DNA evidence, scientists have constructed this phylogeny of primates.
Life Sciences-HHMI Outreach. Copyright 2006 President and Fellows of Harvard College.