So we come to Darwin

• First into medical school (forced by his parents)

• Then, after dropping out, into the seminary

• Finally he found his love of taxonomy and entomology and went to go study it

• Darwin set sail aboard _____ ___________(thanks to someone he met while getting his degree in theology at Cambridge). They left in December 1831

A theory is born• Charles Darwin loved Knowledge… even when on the Beagle he was

learning… this time geology• His first landmark philosophy was that _________________________

__________________________________________(theory of uniformity)

• Darwin combined the knowledge of plate movement, with fossil records and current fauna and thought, and thought

• In the 1840s he had finally developed his theory ________________________ __________________________________________________________

• He sat on his theory until competition forced him to publish it

Darwin Returns to England

• With all of his data Darwin returns and starts conferring with his collogues about what it all means

• Glyptodonts and Armadillos gave him insight to the possibility of ____________ ______________________

• Galapagos Finches helped him to see the formation of a niche and ___________________ _____________________________________________

Thomas Malthus’ influence• Said that ______________________

___________________… thus disease, famine, homelessness continued

• These things are all caused, or continued from a lack of resources (Darwin believed that ___________________________ ______________________________)

• This lack of resources causes a dying curve as they develop and only a select few will make it to reproductive age alive and viable!

**Humans break this rule and are suffering the consequences of it

Two more important factors• Darwin noticed, and you can too, that the ______________

____________________________________________• Offspring resemble their parents in a way that shows there is

something that is passed on… a ______________ (before genes were understood)

• _____________________________________________________________________________(thanks Wallace) _________________________________________________________________(to survive and reproduce)

Putting it all together• Of the multitude of characteristics,

those that helped an individual survive to reproductive age were passed on more often

• Reproduction is ____________!• Overtime the ____________

_________________and those that are not disappear altogether– THIS CONCEPT IS CALLED

NATURAL SELECTION• Example: Butterfly and pollution

Competition: good then, good now

• Darwin was a thoughtful person… Over the 10 years before the publishing Darwin kept thinking.

• When competition finally forced him to publish his book he had strong evidence, and good, logical arguments

• ____________________________________________________________________________________________________________________

• This vision gave/ gives rise to the total concept of evolution… which has itself evolved over the years… but we’ll get to that later

Fossils• The key to the past… bones and other well preserved tissues

can be the key to the evolutionary path• The fossil record sets fossilized life

________________________• The fossil record gives us a lot of the information that is used

as support for evolution• Earliest fossils were interpreted through the prism of cultural

beliefs, and have had to be reinterpreted since.

Fossilization• Fossils are made when hard bones, teeth,

etc are buried and become stone hard over many years

• ________________________________________________________________________________________________________________________

• The layers on the top were considered more recent, and the deeper the layer the older the fossil

• This ______________, using the stratification was as good as possible but did not necessarily correspond on different continents all around the world.

Interpreting Fossils• Recently the process for determining age has improved with

technology• Now use ___________________

– Use the half life of an element (the time it takes half of the radioisotopes to decay to their stable state) to tell the age of a fossil

• The most common way to date young fossils is using ___________.– All fossils contain carbon, which exists as C12 most of the time but

sometimes as the isotope C14– As time passes the C14 decays into C12. By studying how much C14 is

present in a fossil you can determine its age– Carbons half life is 5,370 years

Macroevolution looks at evolution over a greater time span

• Uses the ______________________… a history of the earth with all the major species that have inhabited it.

• Lists the origin of the earth at ________________ _______________________________Years ago!!!

• Divided into _______________________that mark the major species and climate of that time.

• Ages and relative ages are determined using radiometric dating… uses the half life of an element to determine the approximate age of the specimen.

Continental drift and Pangaea

• Based on fossil evidence, especially of the Jurassic period, there is substantial evidence for the super continent _________________

• It was not the first position nor is the current position a final destination for the continents.

• _______________________and ___________________continue even today

• The concept of being once one, explains the divergent but similar species found all around the globe– Lungfish– Marsupials (Australia's

“mammals”)

Plate Tectonics: the study of continental movement• There are many major

plates within the earth’s surface

• These plates can push away from each other, or run into each other spurting volcanoes, or driving up mountains

• Volcanoes can from islands and more room for bio-diversity

• Colliding continents on separate plates can give rise to enormous mountain ranges like the Himalayas (in India)

Phylogenetic trees show evolutionary history

• Way to organize the historical information we have based on radiometric dating, DNA evidence, etc.

• The bottom-most is the most primitive, ___________________ ____________________________________________________________

• The more branching events the farther diverged the species

When tracing evolutionary history, there are many techniques

• Darwin used these techniques for his evidence and arguments– Biogeography– Comparative Anatomy

• Some came into common use after Darwin’s time– Comparative embryology– Molecular biology

We already talked about these, but a quick review

These techniques came later and, like radiometric dating improved technique

Need to keep homology and analogy separated

• Homologous structures imply a common ancestor. (________________________)

• Analogous structures look similar but have __________________________________ … they were independently generated

Comparative embryology

• Checking evolution by looking at how we start… all the final creatures look very different but they start the same way.– Its like two students turning in

two essays that are ALMOST the same… they are different fonts, different margins, even have the paragraphs in a different order but if you look beyond into the content you can see they came from the same paper (that’s what comparative embryology tries to do)

Molecular Biology• Perhaps the best

evidence for evolution• Actual compares the

DNA of different species… _________________________________________________________

• Shows the progression of common ancestors (remember evolution is NOT LINEAR!!!)

Trees are works in progress• With new technology we

have more accurate pictures of the phylogeny of many species

• Now use protein sequences as well and DNA and RNA comparisons.

• The people who spend their life classifying organisms based on their phylogeny are systematists… they usually focus on one family, order, class or phylum

Systematists have many tools

• Deciding which phylum belongs in which class, or which species are part of which family is tricky business of guess and check– Because the information always changes so do the trees

• Organize phylogeny into _____________________________ charts that show the evolution of one thing from others and identifies the derived characters it acquires along the way

• Involves a quest for the simple answer… which is probably the right answer… parsimony

Systematics depends on phylogeny

• All animals based on their clade and phylogeny are placed into taxa…

• They are distinguished from one another and classified according to their history and current features

Kingdom Animalia

Phylum........ Chordata

(Members of this phylum have a notochord during their early development. A notochord is a rod-like skeletal structure. It disappears or changes as the animal grows.)

Class........ Mammalia(Members of this class have 3 middle ear bones, have hair, and produce milk.)

Order........ Carnivora(Members of this order have teeth that could eat meat.)

Family........ Canidae

(Members of this family share body characteristics such as the shape of the skull and the number of teeth.)

Genus........ Canis(Members of this genus are dogs including wolves and foxes)

Species........ familiarus (This is the domestic dog like Dude!)

Classifications start with Domains and Kingdoms

• Although the exact number of each is debatable all living things fit into one of 3 domains and 1 of five kingdoms based on what they have in COMMON

• The reason for debate is Protista a kingdom based on not being in the other kingdoms, not on having a common feature