Day 17 October 24th Chapter 8 Scribd
-
Upload
amy-hollingsworth -
Category
Documents
-
view
223 -
download
0
Transcript of Day 17 October 24th Chapter 8 Scribd
-
8/3/2019 Day 17 October 24th Chapter 8 Scribd
1/29
Day 17 October 24th Chapter 8
400 million years between humans
and our fish ancestors
-
8/3/2019 Day 17 October 24th Chapter 8 Scribd
2/29
What made humans different?
Moved from inland
Africa to the shores
Collected shellfish, ate
fish (DHA) Your brain is mostly
composed of fat!
Mammals haveplacenta
Mammals drink milk
-
8/3/2019 Day 17 October 24th Chapter 8 Scribd
3/29
http://evolution.berkeley.edu/evolibrary/news/060201_zebrafish
http://evolution.berkeley.edu/evolibrary/news/060201_zebrafishhttp://evolution.berkeley.edu/evolibrary/news/060201_zebrafish -
8/3/2019 Day 17 October 24th Chapter 8 Scribd
4/29
Five primary lines of evidence:
1. The fossil record
2. Biogeography
3. Comparative anatomy and embryology
4. Molecular biology
5. Laboratory and field experiments
-
8/3/2019 Day 17 October 24th Chapter 8 Scribd
5/29
8.17 The fossil record
documents the process ofnatural selection.
Although it has been central to much documentation of the
occurrence of evolution, it is a very incomplete record
-
8/3/2019 Day 17 October 24th Chapter 8 Scribd
6/29
-
8/3/2019 Day 17 October 24th Chapter 8 Scribd
7/29
In Darwins
time, it was
assumed
that thedeeper
down in the
earth a
fossil wasfound, the
older it was.
Relative
Dating
-
8/3/2019 Day 17 October 24th Chapter 8 Scribd
8/29
Happened in North America 55 million years ago
Many branches, not just a straight line
-
8/3/2019 Day 17 October 24th Chapter 8 Scribd
9/29
First found in
northern Canadaand estimated at
375 million years
old, Tiktaalik
fossils appear torepresent a
transitional phase
between fish and
land animals.
-
8/3/2019 Day 17 October 24th Chapter 8 Scribd
10/29
8-18. Geographic patterns of speciesdistributions reflect their evolutionary
histories.
-
8/3/2019 Day 17 October 24th Chapter 8 Scribd
11/29
History Matters
Who arrived first?
Are numerous different habitats available?
In Hawaii, it appears that a finch-like descendant of the
honeycreepers arrived 4-5 million years ago and rapidlyevolved into a large number of diverse species.
The same process has occurred and continues to occur in
all locales, not just on islands.
-
8/3/2019 Day 17 October 24th Chapter 8 Scribd
12/29
-
8/3/2019 Day 17 October 24th Chapter 8 Scribd
13/29
8.19 Comparative anatomy andembryology reveal common
evolutionary origins.
-
8/3/2019 Day 17 October 24th Chapter 8 Scribd
14/29
Ernst Haeckel (1834-1919)
-
8/3/2019 Day 17 October 24th Chapter 8 Scribd
15/29
Homologous Structures
-
8/3/2019 Day 17 October 24th Chapter 8 Scribd
16/29
Similarities common ancestor
Differences adapted to environment
For example, look at the hands offour primates: tarsier, gibbon,chimpanzee, and human. Despite thesimilarities in their hands, thedifferences are what makes eachmost suitable for its way of life. The
tarsier leaps and clings, and has largefinger pads to help it do this. Thegibbon swings from the trees, so haslong, strong fingers for swinging. Thechimpanzee may be able tomanipulate very crude tools with itsstubby thumb, but the humans
thumb faces the forefinger, whichprovides dexterity for countlesspurposesfrom threading a needleto mountain climbingfrom carvingwood to buttoning a shirt.
-
8/3/2019 Day 17 October 24th Chapter 8 Scribd
17/29
Vestigial Organs
A vestigial organ is a part of the body that serves no use. The
appendix is one example of a vestigial organ; wings on an ostrichare another. The human body has several vestigial organs,
including the tail bone, wisdom teeth and muscles in the ear.
-
8/3/2019 Day 17 October 24th Chapter 8 Scribd
18/29
Vestigial Structures
-
8/3/2019 Day 17 October 24th Chapter 8 Scribd
19/29
Convergent Evolution
Analogous structuresall developed fromdifferent original
structures.
-
8/3/2019 Day 17 October 24th Chapter 8 Scribd
20/29
8.20 Molecular biology revealsthat common genetic sequences
link all life forms.The genetic code provides our fourthline of evidence that evolution occurs.
-
8/3/2019 Day 17 October 24th Chapter 8 Scribd
21/29
DNA Similarities and Differences
Related vs. unrelated individuals
The more distantly you and anotherindividual are related, the more your DNAdiffers.
-
8/3/2019 Day 17 October 24th Chapter 8 Scribd
22/29
Scientists ask the questionDoes
race exist?
The Human Genome Project
found all humans to have a
99.9 % similar geneticcontent and identity, but this
is challenged by a new more
detailed research suggesting
a higher genetic diversity,with further medical and
evolutionary implications.
-
8/3/2019 Day 17 October 24th Chapter 8 Scribd
23/29
-
8/3/2019 Day 17 October 24th Chapter 8 Scribd
24/29
DNA Similaritybetween Two Species
Compare their DNA sequences forindividual genes.
In Rhesus monkeys, 138 amino acids outof 146 are the same as those found in
human hemoglobin.
-
8/3/2019 Day 17 October 24th Chapter 8 Scribd
25/29
Recency of Common Ancestry
Estimates of evolutionaryrelatedness made from:
Comparative Anatomy
Embryology The Fossil Record
Molecular Clocks
-
8/3/2019 Day 17 October 24th Chapter 8 Scribd
26/29
8.21 Laboratory and field experimentsenable us to watch evolution in progress.
A fifth line of evidence for the occurrence ofevolution comes from multigeneration
experiments and observations.
-
8/3/2019 Day 17 October 24th Chapter 8 Scribd
27/29
Changes in the Frequencyof the Various Alleles
-
8/3/2019 Day 17 October 24th Chapter 8 Scribd
28/29
-
8/3/2019 Day 17 October 24th Chapter 8 Scribd
29/29