12 Upper Gower Street, London

Charles and Emma Darwin made this their home from their marriage in January 1839 until September, 1842.

The 5 year voyage of the Beagle

Using this map…

Please match the tortoises with the islands, and summarize the connections you made.

Please discuss climate, natural selection and speciation. Figure 1. Galapagos

tortoises: One with a “saddle” back from Espanola or Pinta Island and one with a dome back from Santa Cruz Island. Note the difference in shell shape as it allows or impedes extending the neck to higher foliage.

Some of Darwin’s original notes

• http://darwin-online.org.uk/content/search-results?freetext=tortoise

• Take a look at Darwin’s notes while on board the Beagle…

http://www.ucmp.berkeley.edu/history/malthus.html

“On October 1838, that is, fifteen months after I had begun my systematic inquiry, I happened to read for amusement Malthus on Population, and being well prepared to appreciate the struggle for existence which everywhere goes on from long- continued observation of the habits of animals and plants, it at once struck me that under these circumstances favourable variations would tend to be preserved, and unfavourable ones to be destroyed. The results of this would be the formation of a new species. Here, then I had at last got a

theory by which to work".Charles Darwin, from his autobiography. (1876)

Remember Natural Selection?

• What are the key components?

• How does this relate to the finches? The tortoises?

• What would islands have to do with it?

Charles Lyell: Age of the earthhttp://en.wikipedia.org/wiki/File:Earth_seafloor_crust_age_poster.gif

How do scientists determine a “species”? http://www.ehow.com/facts_6023459_difference-

between-mules-donkeys_.html• How, do you think, did Darwin determine whether or not

the organisms he saw on his journey were or were not different species?

• A mule is not a species; a mule is the infertile offspring of a male donkey and a female horse. The donkey, on the other hand, is a

particular species.

Tortoises are same species, but different variations!

• The smaller, saddle backed tortoises are from Espanola and Pinta Islands and the larger domed tortoises are from Santa Cruz

Using your family pictures and maps and images of Galapagos

tortoises

• Do you notice a pattern connecting traits in your own or others’ families?

• What is the link between vegetation on the islands to physical traits of the tortoises? (can you describe it using a term?)

• Why was this link not likely, given the cultural info.?

http://evolution.berkeley.edu/evolibrary/article/_0/history_14

• visit to the Galapagos Islands in 1835 helped Darwin formulate his ideas on natural selection. He found several species of finch adapted to different environmental niches. The finches also differed in beak shape, food source, and how food was captured.

                                                     

                                                                                                                                                                                                                                                                                                                                                                                                                  

A visit to the Galapagos Islands in 1835 helped Darwin formulate his ideas on natural selection. He found several species of finch adapted to different environmental niches. The finches also differed in beak shape, food source, and how food was captured.

Some audio of the Beagle http://darwin-online.org.uk/BookoftheWeek.html

• Darwin's Beagle Diary--audio recording       of excerpts from Darwin's popular account

       of his voyage of exploration.  This link       takes you to an external website.  To       return here, you must click the "back"

       button on your browser program.       (length = 68 mins, 19 secs)

http://darwin-online.org.uk/BookoftheWeek.html

Cladogram showing common descent:

http://en.wikipedia.org/wiki/Phylogenetic_tree

http://www.nature.com/nature/journal/v421/n6921/images/nature01400-f1.2.jpg

In the year 1758, Carol Linnaeus proposed four subcategories of Homo sapiens: Americanus; Asiaticus;

Africanus; and Europeanus. (Systema naturae)

Please discuss

• Darwin developed a hypothesis that species change over time. The journey to the Galapagos Islands and Darwin’s study of tortoises supported this hypothesis and he was able to apply this to humans (Homo sapiens) as well.

• From our studies, what theory did this hypothesis develop into?

• What terms/vocabulary are referred to here?

Like Darwin, Huxley studied natural history while traveling on a naval ship. Initially, Huxley did not accept evolution at all. But Darwin converted him with the On the Origin of Species, and Huxley mused afterwards, "How extremely stupid not to have thought of that!"

Although he was much more than a defender of Darwin -- he led the movement toward the professionalization of science, for example -- Huxley is best known for his public exchange in 1860 with Bishop Samuel Wilberforce. The bishop, a clever, witty debater, opened himself to attack by making a gentle joke about Huxley's ancestry. Huxley, furious, replied famously to the effect that he would rather be descended from an ape than a bishop.

Alfred Wallace and others: What about science, how it is discovered, thought about, presented?

To do:

• http://www.pbs.org/wgbh/evolution/educators/lessons/lesson3/act2.html

• Note: this shows the many areas of science that support common descent and natural selection

• http://www.indiana.edu/~ensiweb/lessons/chr.jpeg.html

• Note: this site uses our knowledge of classification, karyotypes and shows the common ancestor (not descent of ) humans and(not from) primates

• http://www.simplescience.org/Lessons/Biology/AH/Lesson0.htm

• Note: an activity showing homologous structures

http://www.indiana.edu/~ensiweb/lessons/chr.jpeg.htmlhttp://www.indiana.edu/~ensiweb/lessons/chr.jpeg.html

Role play/debate on Monday

• Darwin wishes to present his theory that humans are all of the same species, on a cladogram.

• Given the culture at the time and role cards, you will debate how Darwin’s theory impacts the culture.

• I will have hot chocolate and tea. Please BYOM!

Some Reflection Q• How is the information about humans relating to chimpanzees

discussed?

• How is the notion of slavery at the time supported? • How do Darwin’s writings impact the action of slavery and “ranking”

of humans?

• He has already published papers on his thoughts about the similarities between tortoises but the culture at the time (and Darwin) thought the earth was too young. What was the influence of geology on Darwin’s interpretation?

• What do the other scientists of the time think? How do they react to Darwin’s work? Who are his supporters and who are his detractors?