Great Ideas of Biology

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1 Great Ideas of Biology Lecture 1 Alan Morti

2 The notes to accompany this lecture series are provided for the educational use of the course participants. It is believed that images may be used for educational purposes and are sighted where necessary. Full lecture notes have been provided due to limited sight lines in the classroom. Please note: These notes provide the background material. The actual lectures will include content and explanations which may or may not be represented in detail in the notes provided. Expect the material to evolve throughout the course based on interests of the participants. Alan Mortimer PhD

3 Before We Start Logistics Lecture materials About me About you Questions during lectures

4 Great Ideas of Biology Our approach to biology has been different than the approach to physical sciences There are a lot more pieces to the puzzled There is a focus on details There must be some large scale ideas that traverse all of biology

5 Great Ideas of Biology Sir Paul Nurse FRSE President of the Royal Society Director of the Francis Crick Institute, London Nobel Prize in Physiology or Medicine

6 Great Ideas of Biology 1. Evolution 2. The cell as the basic unit of life 3. Genetics and DNA 4. The infectious nature of disease 5. Immunity 6. Current issues and anti- ideas

7 Don t Panic

8 Evolution

9 July 1, 1858 Paper presented at the Linaean Society London England by Charles Darwin and Albert Russel Wallace Read by Secretary Wallace in Malaysia, Darwin in mourning No reaction that evening Other papers, lots of society business It was accepted for publication in the society transactions

11 Origin of Species Significance became apparent over the following year So did the controversy Origin of Species was published November 1859 On the origin of species by means of natural selection or the preservation of favoured species in the struggle for life

13 Origin of Species Origin of Species and evolution has become part of our everyday language But if one looks at it from the viewpoint of the day, this is certainly one of the great pieces of scientific reasoning

14 A Great Idea Why would anyone think that

15 A Great Idea Could all be related to each other?

16 A Great Idea And especially related to:

17 Back to the Beginning 19 th Century England Industrialization Travel, Exploration and Colonization Richard Burton, Livingston, Franklin Highly Christian Society Church of England Church schools including Cambridge University The beginning of a upper middle class

18 The Story Begins Charles Darwin Born Feb 12, 1809 (Shrewsbury) Father was a prominent physician Grandfather was an eminent Botanist From a young age he liked being a naturalist Wealth and privilege allowed him to do so Father wanted him to be a physician Enrolled in Edinburgh at 16 to study medicine

19 The Story Begins Charles Darwin Didn t work out; (he couldn t stand the sight of blood) 18 enrolled at Cambridge. Continued to collect and meet other naturalists including Henslow (botany), Sedgwick (geology) Greatly appreciated the work of William Paley (Evidences of Christianity) and William Herschel (inductive reasoning) John Stevens Henslow recommended him as a supernumerary companion and naturalist to Robert FitzRoy on the second voyage of the Beagle

20 The Beagle Dec 1831 to Oct 1836 Figure 1.1

21 The Beagle The wide variety of geographic conditions and the length of time spent in specific locations allowed for Detailed study Comparison of locations Key locations: Patagonia (fossils) Galapagos Islands Australia

22 Galapagos Islands Regular stop for sailing ships Series of volcanic cones (18 major islands) ~100km east of Ecuador HMS Beagle in the Galapagos, 17 October p.m. by John Chancellor.

23 Galapagos Islands He found birds similar to those on the mainland, but different from island to island Different species of finches lived in different geographical conditions He noted that the environment was very similar to the Cape Verde Islands, but the birds occupying the islands were very different. Both resembled more closely the closest mainland birds

Finches Figure 1.2 Darwin s Finches http://www.pbs.

24 Finches Figure 1.2 Darwin s Finches

25 Galapagos Islands Darwin made similar observations regarding the giant tortoises

26 The First Ideas Darwin noted in journal: If God had created creatures most suitable to an environment why then are the birds found on Galapagos and Cape Verde different to each other and why are they each more similar to their respective mainland species This from a man who, upon departure had greatly appreciated Payley: if a pocket watch is found on a heath, it is most reasonable to assume that someone dropped it and that it was made by one or more watchmakers, and not by natural forces.

27 The First Ideas Australia: Darwin noted that marsupials occupied conditions which, on other continents, would have been occupied by mammals Patagonia: Collected fossils that looked much like animals he knew Understood that strata represented a continious time series

28 Upon return Lots of collections and samples to analyse He had very good connections Fossil samples were delivered to Richard Owen and to Charles Lyell 5 extinct relatives of existing mammals only gigantic Armadillo Sloth Armoured sloth A rodent with a skull 2 ft long Llama that Darwin had labeled as a Mastidon

29 Upon return Bird collection was given to Zoological Society Analysed by John Gould Darwin s birds which he though were a mixture of grosbeaks, finches and blackbirds were actually 12 separate species of finches He was able to plot the location of each species on each island (needed other peoples records to support his own)

30 The Pieces Come Together The idea of transmutation of species started to develop on the Beagle voyage Darwin moved to London to work with leading scientists on his collections The solid scientific information upon return convinced Darwin that species did change in response to local environment The question that he had yet to work out was how

31 Answers in Strangest Places While in London he stayed with his brother Erasmus friend of Harriet Martineau who promoted Malthusianism, the basis for Poor Law Reforms designed to prevent the poor from overproducing Thomas Malthus: Essay on the principle of population (1778) British East India Company Humanity would grow faster than the food supply Therefore humanity was doomed

32 The Theory Complete Lyell on learning of Malthus said why did we not think of that It provided the final piece for the puzzle The idea was formed in 1837

33 The Theory There are several basic pieces to Theory of Evolution by Natural Selection Species overproduce There occurs variation in the offspring Among the variations, those most able to reproduce in a given environment will dominate Darwin recognised that environment was multi-faceted

34 From Idea to Publication Formulation of the theory was complete 1837 yet first presented in Darwin wanted to make certain that he had covered all possible objections He started out to produce a multi-volume (12-17) treatise He was also concerned that his arguments would not be taken seriously because he would be seen as an amateur

35 From Idea to Publication He embarked on a study of barnacles and became the expert in classification of barnacles and wrote a book. He then studied breeding practices in domesticated animals (which was becoming more common) particularly cattle sheep and pigeons He could demonstrate that there was natural variation and that traits could be selected

36 Alfred Russel Wallace

37 Alfred Russel Wallace Grew up in modest circumstances in Wales and Hertfordshire Six years of grammar school Apprenticed as a surveyor Work as a surveyor for 8 years Became a skeptic of organized religion

38 Alfred Russel Wallace Became a self-employed specimen collector Private collections we extremely popular in the upper classes Spent 4 years in Brazil in Amazonia Mapped the Rio Negro Also studies peoples and languages of the region Gained acclaim and funding from the Royal Geographical Society which partially funded his next trip to Malay Archipeligo

39 Alfred Russel Wallace Spent 8 years ( ) travelling among the islands and collecting Almost died several times Noticed: Variation in similar animals between islands Adaptations of animals to local conditions Very different animals living in almost identical conditions ( Lumbok and Bali)

40 Alfred Russel Wallace

41 Alfred Russel Wallace

42 Alfred Russel Wallace

43 Alfred Russel Wallace By 1858 he had developed the ideas of natural selection and biogeography He sent a letter describing his idea to Darwin He had read Darwin s early work Was the only person he could think of that might take the idea seriously

44 Publish or Perish In 1858 Darwin received a copy of a paper by Alfred Wallace from his base in Borneo On the tendency of varieties to depart indefinitely from the parental type Darwin (at Lyell s urging) had finally started to write his species book in 1857 Now he stood to be scooped by someone who had similar ideas (almost 20 years later)

45 Publish or Perish Fortunately mail (and science) moved slowly Lyell and Hooker convinced Darwin to write a précis of his magnum opus. This would take some time They agreed to a slightly shorter version and Hooker and Lyell arranged to have it read at Linnaean Society together with Wallace s paper It was the publication of the book the next year that established Darwin as the founder of the theory

46 Perceived Problems Origin of Species does not deal with Human beings or sexual selection Darwin delayed the publication of these ideas because he expected controversy 1879 The Decent of Man and Selection in Relation to Sex

47 Humans in the Theory It is longer than Origin of Species

48 The Victorian Era Perceived competition with inferior classes Era of slavery Based on superiority of Europeans race Had to wait for the emancipation movement

49 The Victorian Era The first Neanderthals were discovered Seen as a separate, unsuccessful species Some related them to Irish Celts

50 The Victorian Era While the role of the individual was becoming important the Church still dominated general thought Takes time to change foundations of society after almost 2000 years Think of children s hymns The Lord God Made Them all etc. Only the beginning of separating not knowing from faith and religion

51 Perceived Problems Amateurism Discontinuity of fossil records Fossil species seem to appear Sources of variation Lack of evidence to support human evolution Observational time scales

52 Neo-Darwinism Darwin s Theory preceded Mendelian Genetics The concept of Heritable Unit The discovery of DNA and Genes These concepts have strengthened the overall theory by explaining the why Provide an explanation for variability required by evolution

53 Evolution follows a quasi-random path We can t really demonstrate the randomness of the path This can be seen in development of features such as the eye In humans blood vessels overlay the retina In octopus the eye developed from a different part of the brain

54 A Great Idea

55 Darwinism vs Creationism Naturalist Philip Goss (1857) stated: the world as it is, fossils and all, was created in a single act of creation A member of the Plymouth Brethren Creationism has been largely an American phenomenon since the 1920 s Saw WW1 as an attempt to use survival of the fittest to justify war

56 Darwinism vs Creationism Could be based on any or all of: Distrust of science and scientific explanations Populace approach: don t tell me what I know Supported politically American Christianity as a justification for American Capitalism Two fundamentally different views of the world

57 Today s Questions Epigenetics Adaptations that are acquired in one generation can be passed on to offspring Coded randomness

58 Marcel Proust the real voyage of discovery consists not in seeking new landscapes but in having new eyes

59 Observable Evolution On a human time scale it is difficult to observe evolution in progress. A typical human generation is ~20 years. Less than 8 generations since Darwin wrote Origin of Species ~120 generations since there has been recorded history

60 Impacts of Evolution Bacteria generation time ~30 minutes or 17,500 generations per year! One year of bacterial growth has as many reproduction occasions as 350,000 years of human history It is important to note that human reproduction is different from that of bacteria

61 Antibiotic Resistance Antibiotics were first developed When used over a large population there will be some surviving bacteria that aren t affected by the particular antibiotic. This is because bacteria have a very error prone reproduction system Those that survive have very little competition for resources and flourish.

63 Antibiotic Resistance Causes include Overuse of antibiotics Poor sanitation leading to antibiotics in the environment Large bacterial load

64 Antibiotic Resistance Major concerns for Anti-Microbial Resistance Tuberculosis Malaria MRSA (Methicillin-Resistant Staphylococcus Aureus) HIV

65 Dissemination of antibiotics and antibiotic resistance within agriculture, community, hospital, wastewater treatment, and associated environments. Davies J, and Davies D Microbiol. Mol. Biol. Rev. 2010;74:

66 Worldwide distribution of different classes of CTX-M β-lactamases (first identified in 1989). Davies J, and Davies D Microbiol. Mol. Biol. Rev. 2010;74:

68 Caveats Single cell organism Does not address issues of inter-cell relationships i.e. inter-cell communication How does one look for the major changes comparable to aquatic/terrestrial species Addresses one single trait, not the complexity of animal evolution

The Origin of Species The Making of a Theory

The Origin of Species The Making of a Theory READING PRIMARY SOURCES: DARWIN AND WALLACE OVERVIEW This activity serves as a supplement to the HHMI short film The Origin of Species:. Students read and analyze excerpts from texts written by Charles