Philosophical presuppositions of evolutionary biology FFDI Zagreb, 20-25 April 2015

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Philosophical presuppositions of evolutionary
biology FFDI Zagreb, 20-25 April 2015

1. Aims method of this lecture
2. The received view Aristotles biology
3. Evolutionary ideas until Darwin
4. History of evolutionary thought from Darwin to
   the present
5. Evolution Theory-structures and concepts
6. Evolution between science and world-view
7. Summary discussion

• Prof.Dr.Dr. Winfried Löffler
• University of Innsbruck
• Department of Christian Philosophy
• Karl-Rahner-Platz 1
• A-6020 Innsbruck, Austria
• winfried.loeffler_at_uibk.ac.at
• www.uibk.ac.at/philtheol/loeffler

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1. Aims and method of this lecture

• Aims
• Some basics about current evolutionary biology
• Some basics about its historical backgrounds
• Understand its peculiar theoretical status
• Distinguish between scientific theory and its
  ideological interpretations / reductionisms
  
• Misunderstandings of anti-evolutionism
• Method historical (2-4, partly 6) to understand
  conceptual backgrounds

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2. The received view Aristotles biology

• 2.1 Life and Works
• Aristotle (384-322) today usually seen as
  philosopher, but first big encyclopedist
• Almost all scientific disciplines
• - Physics, biology, physiology, meteorology,
  psychology,
• - economics, politology, aesthetics / poetology
• - ethics, rhetorics, philosophy of language,
• - philosophy of science
• - general philosophy (first philosophy,
  metaphysics)

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• Influential merits in the philosophy of science
• - Important basic concepts (substance/accident,
  potential/actual, matter/form, efficient
  cause/final cause)
• - Classification of the scientific disciplines
  (theoretical/practical/poietical) (episteme /
  historia / techne)
• - Structure of scientific arguments (Prior
  Analytics, syllogism)
• - Structure of scientific classifications
• - Structure of an empirical science (empirical
  first sentences logical derivations from
  them) overcoming Platonism
• Heavy influence on Western thought!!!

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• 2.2 Biological writings
• Historia animalium (History of Animals) - see
  later
• De partibus animalium (Parts of Animals)
• De generatione animalium (Generation of Animals)
• Smaller writings (On movement of animals, sleep
  and sleeplessness, breathing, life and death
  etc.)
• Biggest part of his work is natural science!
• Interestingly little interest in medicine (son
  of a healer!) and botany

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• 2.3 Aristotles method in biology
• Empirical (broad sense) with speculative
  assumptions
• Classification of phenomena plus question for
  causes (4 causes)
• Reports of experts, own observations
• Maybe experiments, anatomical sections (stages
  of fertilized eggs)
• Only scarcely quantification (lengths) not
  weights, food intake etc.
• Only scarcely ecological view (what it eats)
• Aim Collection/classification of facts
  (historía) and research for causes

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• 2.3 Aristotles method in biology
• Teleology without design
• Natural things seen as functional units with
  functional parts
• Teleological world-picture
• Chief pattern of explanation final explanation,
  what is it good for?
• Example why do animals with a lung also have a
  neck? De part.An.III,3
• (Roughly) Bipartite lungs need some tube to
  partition the air that tube needs a certain
  length, hence the windpipe. Hence also, the
  oesophagus/jednjak. Hence, the necessity of a
  neck. (Fish dont need one). The vicinity of
  windpipe and oesophagus is technically bad and
  would cause trouble hence, nature contrived the
  epiglottis.
• Nature as a whole is rational. Natura nihil facit
  frustra. Form follows function
• BUT No external design plans.

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• 2.4 Aristotles taxonomy
• 550 species according to morphological criteria,
  300 re-identifiable today
• Groups and similarity observations e.g., all
  live-bearing quadrupeds have lungs and windpipes
• Attempts to a classification of the whole range
  of animals, morphological features not always
  consistent and sometimes wrong
• Man is included as a sub-class!

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• 2.4 Aristotles taxonomy
• An example from HA IV 1, 524a3-20 The octopus
  uses its tentacles both as feet and as hands it
  draws in its food with the two that are placed
  over its mouth. The last of them, which is very
  sharp and is the only one which is whitish in
  colour and bifurcated at the tipit is made so as
  to uncoil on the rhachis side (the rhachis being
  the smooth surface of the tentacle away from the
  suckers)this one it uses in the act of
  copulation. In front of the sac and above the
  tentacles they have a hollow tube, by means of
  which they discharge from the sac any sea-water
  which may have come in while taking food into the
  mouth. The animal can move this tube to right and
  to left it also discharges its ink through it.
  It swims obliquely in the direction of the
  so-called head, stretching out its feet and by
  swimming in this way it can see forwards (since
  its eyes are on top), while its mouth is at the
  rear. So long as the animal is alive, the head is
  hard and as it were inflated. It takes hold of
  things and retains them with the underside of its
  tentacles, and the membrane between its feet is
  kept extended in its entirety. If it gets on to
  the sand, it can no longer retain its hold.

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• Aristotles taxonomy (roughly)
• Animals with blood (today vertebrates)
• Live-bearing quadrupeds
• Egg-laying Quadrupeds
• Birds
• Fish
• Cetacea (sea mammals)
• Egg-laying footless (snakes)
• Live-bearing footless (vipers)
• Man
• Animals without blood
• Cephalopods
• Molluscs
• Insects
• Crustaceans

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• 2.5 The stability of species
• Fundamental for 2300 years.
• Minimal traces of evolutionary ideas?
• (1) Libya always produces something new (De
  gen.an. II,7)
• crossing of animal species at waterholes
  reflection about the infertility of hybrids
• (2) Reflection about Empedocles (5.century BC)
  mythical explanation of the origin of life
  plants first, then parts of animals, then
  animals, only the useful ones survived
• Aristotle random combinations would not have
  survived (Phys. II, 8)
• (3) Knowledge about variation not all animals
  conform to species, monstrosities, freak animals
  etc. (Not worrifying, just freaks of nature)

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• 2.6 Astonishing pioneerhoods and errors
• Pioneerhoods
• Sexual life of octopus
• Opposition to preformation theory / homunculus
  theory of the sperm (until 19th century!).
  Epigenetic, step by step, formation of organs
  the important ones for the genus-membership
  first.
• Errors
• Bison throws feces 7m for defense
• Women have less teeth
• Dayfly has only 4 legs
• Speculations
• Parthenogenesis and other forms of reproduction
• Procreation (in mud etc.) until Pasteur, 19th
  century!
• Brains serve to cool blood
• Women are incomplete men (more influence of
  katameria than of sperm)
• Women get soul later, birth rates m/f have to do
  with winds

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• 3. Evolutionary ideas until Darwin
• 3.1 Some aspects of biology after the middle ages
• Renaissance
• Excursions, geograph. discoveries, herbaria,
  museums
• flourishing of anatomy (Andreas Vesalius, Fabrica
  (1543 De humani corporis fabrica libri VIII)
  public section of corpses previously unknown
  exactness descent-line apes pygmies
  (Plinius!) man)
• 17th cent.
• new science of nature (Bacon, Galilei)Experiments
  (planned variation of conditions, protocols)
• New tools of observation microscope, telescope
  discovery of micro-organisms, fine structures,
  insect development
• Physico-theology speculative preformationism
  (1695)(hot discussions 18th cent.
  (Spallanzani), end 1830!)

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3.2 Carl von Linnés taxonomy

• Various attempts to classifications, morphology
  comes in focus (microscopes!)
• Tension Theory still Aristotelian (tree /
  pyramid), experienceshows multiplicity and
  similarities across branches
• Natural history becomes a discipline of its own
  
• Carl von Linné (Linnaeus), 1707-1778 Swedish
  medic and botanist
• Reform of taxonomy, 3 merits
• New system of plants, with classification method
  (according to number and structure of
  reproduction organs sexual system)Systema
  naturae 1735 Genera plantarum 1737 etc.
• Binary nomenclature (instead of descriptions),
  e.g. Sambucus nigra (sambucus genus, sambucus
  nigra species)
• Terminology for the parts of plants

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3.2 Carl von Linnés taxonomy

• Backgrounds of Linnés thought
• Objective structures in nature, ideas of the
  divine creator.
• Not Aristotelian essentialism, but rather
  Enlightenments ideal of ordering
• Does classificatory relatedness imply anything
  about historical relatedness?
• Does the Systema point to a relation?
• - Linné understood it as an artificial system
  with the task of ordering/quick finding natural
  system as final project at horizon. Growing
  discontent about Linnés artificiality.
• - Some unclear remarks about an origin of plants
• - Controversial how firmly he believed in the
  stability of species

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3.3 Early French speculations about evolution

• Georges Buffon (Histoire Naturelle, 36 vols.,
  1753-1788)
• Complexity and similarities in nature make a
  Linnéan classification impossible. And species
  is an abstractum there are individuals
• Procreation and change, by climate etc. Related
  species might have common ancestors, maybe one.
  Earth out of a collision sun-comet.
• Evolutionary scale/ladder instead of Linnés
  hierarchical classification
• Evidence similar anatomy across many species
  (donkey/horse, man/ape, mans foot / horses foot
  etc.) rudimentary, useless organs
• Indirect message EITHER God made the species by
  variation of few plans (great!), OR they have a
  common history. (Officially, the first)

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3.3 Early French speculations about evolution

• Georges Cuvier (1769-1832), Étienne Geoffroy
  Saint-Hilaire (1772-1844) and the Paris Academy
  Dispute 1831 Idealist versus evolutionary
  morphology?
• Cuvier King of functional anatomy, fine
  drawings, function determines structure,
  structure allows conjecture to function.
  Reconstruction of died-out animals out of a few
  bones.
• Four basic construction plans of animals
• Yet firm opposition to any evolutionary change
  (cats from Egypt, )
• Fossils are just extinct species, in
  global/regional catastrophes.
• No intermediate forms in fossils
• Geoffroy St.Hilaire Research in homologies (e.g.
  gill bones in fish ear bones in humans
  vertebrate is similar to inverted worm (nerves at
  back, intestinal at front). Hence, change of
  species, common ancestry.
• Political relevance (1) not ideas of God (2)
  ...if not even nature is stable?

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3.4 Romanticist Philosophy of Nature and
Morphology

• Johann W. von Goethe (1749-1832)
• morphology instead of comparative anatomy
  plants and animals represent certain ideal
  shapes/forms/con-struction plans (mostly
  superficial, restricted to outer form)
• speculations about construction plan of a
  Urpflanze (ideal plant) which is realized in
  variants in real plants
• Postulates that skull bones are modified rib
  bones
• Discovers the intermaxillary bone in human
  embryos since humans represent general mammal
  plan, and all other mammals have it, it must be
  somewhere - in embryonal development!
• Göttingen School (Carl Friedrich Kielmeyer,
  Johann Friedrich Meckel, Lorenz Oken, influenced
  by Fichte and Schelling) Recapitulation
  Development of the embryo recapitulates animals
  of lower complexity
• Partly empirical (embryology, anatomy), partly
  philosophical formative power of nature etc.
  idealist great chain of beings

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3.4 Romanticist Philosophy of Nature and
Morphology

• Richard Owen (1848) Theory of archetypes
  (ideal design plans). Background similar organs
  in very different animals (moles hand
  dolphins fin have same bones!) cannot be due to
  environment.
• Archetype of all vertebrates
• Terminological proposal, used till today
• Homologous organ same construction, different
  function (e.g. moles hand, dolphins fin)
• Analogous organ different construction, same
  function (e.g. birds and butterflys wing)

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3.5 The first evolutionary theory Lamarck 1809

• Jean Baptiste de Lamarck (1744-1829) Philosophie
  zoologique (1809)
• Lamarckism today inheritance of individually
  acquired characteristics, usually seen as
  overcome since Darwin partial revival today
• First evolutionary theory a theory that how
  species change in the course of time.
• Simple forms of life emerge constantly from
  anorganic matter, procreation hence, no common
  ancestry
• Inner tendency to higher development,
  complexifying force le pouvoir de la vie
• Organisms adust behaviour to environment and
  inner state
• Use/disuse of organs leads to growth/change of
  organs (e.g. neck)
• and that change is inherited!
• As with Geoffroy St.Hilaire later politically
  dangerous ideas

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3.5 The first evolutionary theory Lamarck 1809

• Jean Baptiste de Lamarck (1744-1829) Philosophie
  zoologique (1809)
• First Law In every animal which has not passed
  the limit of its development, a more frequent and
  continuous use of any organ gradually
  strengthens, develops and enlarges that organ,
  and gives it a power proportional to the length
  of time it has been so used while the permanent
  disuse of any organ imperceptibly weakens and
  deteriorates it, and progressively diminishes its
  functional capacity, until it finally
  disappears.
• Second Law All the acquisitions or losses
  wrought by nature on individuals, through the
  influence of the environment in which their race
  has long been placed, and hence through the
  influence of the predominant use or permanent
  disuse of any organ all these are preserved by
  reproduction to the new individuals which arise,
  provided that the acquired modifications are
  common to both sexes, or at least to the
  individuals which produce the young.

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3.6 Erasmus Darwin (1731-1802) and a widely
forgotten Anonymous Robert Chambers (1844)

• Erasmus Darwin (grandfather of Charles Darwin and
  Francis Galton)
• Speculative views about Lamarck-style evolution
• Would it be too bold to imagine, that in the
  great length of time, since the earth began to
  exist, perhaps millions of ages before the
  commencement of the history of mankind, would it
  be too bold to imagine, that all warm-blooded
  animals have arisen from one living filament,
  which the great first cause endued with
  animality, with the power of acquiring new parts,
  attended with new propensities, directed by
  irritations, sensations, volitions, and
  associations and thus possessing the faculty of
  continuing to improve by its own inherent
  activity, and of delivering down those
  improvements by generation to its posterity,
  world without end!
• Glimpse of natural selection
• R. Chambers Vestiges of the Natural History of
  Creation (1844)
• Popular science book, rather speculative, many
  errors
• Author Robert Chambers, Scotch writer, anonymous
• Variability of species Man descends from simpler
  forms of life
• Popularity and (slowly starting) excitement

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4. History of evolutionary thought from
Darwin to the present

• 4.1 Charles Darwin (1809-1882) life and works
• Son of a religion-skeptic physician unitarian
• Studies briefly medicine, natural history,
  theology future parson?
• No professional education as a scientist (biology
  not yet established!)
• Invitation to travel on mapping-ship Beagle
  1831-36
• Collects, studies, draws, sendssamples home
• Initially only few doubts about stability of
  species
• Influences
• Charles Lyell (geologist, big changesof the
  earth surface but rejectsLamarckism species
  are createdthey die out due to external change,
  and suppression by other species)
• Richard Owen and Romantics
• Erasmus Darwin
• Lamarck (via Robert E. Grant!)

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• Increasing doubts in Lyells biology (not in his
  geology!)
• released domestic animals adapt quickly to new
  environment
• two similar ostrich species in overlapping areas
  (why does the one not repress the other one?)
• why do species dies out without change in
  environment?
• why are died-out mammals replaced by other,
  similar ones?
• the finches from the Galapagos islands -
  related with each other, related with animals on
  the continent, - different birds in similar
  habitats!- No clear-cut line species -
  variety

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• Back in Cambridge
• Orders his findings, discusses (with Lyell, Owen,
  J. Gould (finches!))
• Early speculations about an explanation for
  relations
• 1837 first sketch I think, insight that
  species must be changeable
• Darwins speculations still /- Lamarckist
  - changes/variations are always useful, since-
  adaptation to environment as an embryo,
  geograph. isolation may cause new species -
  changes are inheritable
• 1838 reads Thomas Malthus Essay on the
  Principle of PopulationPopulations have
  tendency to grow infinitely, but limited
  resources cause concurrence and limit growth,
• ? Darwin Selection not as embryo, but after
  birth. Theory of natural selection was /-
  finished by 1839 (diaries).

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• The Theory of Natural Selection
• Random, undirected, inheritable variations
  PLUS
• natural selection under the pressure of the
  environment, concurrence for food etc.
• may in the long run lead to the emergence of
  adaptive (useful) change and new species.
• I.e., variations need not be perfect anymore. Old
  idea of perfect adaptation (from natural
  theology!) abandoned. Variations need just be
  slightly better.
• A manuscript was finished by 1842. Why not
  published? (1) Fear of scandal (Vestiges 1844!)?
  (2) Darwin had not yet a good idea for the
  ramifications / divergences in the changes.
• After 1854 Sympatry (different species in same
  area) is more important than Allopatry (different
  species in isolated areas). Coherent with the
  facts. Reason Big areas have more ecological
  niches!

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• The Publication and its effects
• 1856 Darwin presents his ideas to Lyell etc.,
  friends urge to publish
• 1858 Alfred Russel Wallace sends a manuscript to
  Darwin, similar ideas
• 1858 Common paper by Darwin and Wallace, Wallace
  admits priority
• 1859 On the Origin of Species by Means of Natural
  Selection
• Public effect
• In England dampened by a theol. discussion
  aboutcorrect Bible interpretation 1860, and
  Vestiges
• John Herschel (astronomer, 1792-1871)
  unscien-tific, since only statistical
• Thomas Huxley (Darwins Bulldog) tries to
  elicitcultural discussion, free universities, no
  religion
• Not even whole church opposes. Still excitement.
• In France Cuvier dominates, no big interest
• In Germany bestseller, quick translation,
  popularizedby Ernst Haeckel (materialist
  reading!)

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• Later Publications
• 1871 The Descent of Man (no big scandal
  evolution of moral behavior)
• 1872 The Expression of Emotions in Animals and
  Man
• Works about coral reefs,
• plant fertilisation, rainworms, etc.
• Darwin and religion
• 1851 Death of his daughter, loss of religious
  faith, respectful agnostic
• 1882 Tomb in Westminster Abbey

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• 4.2 The Five Basic Tenets of Darwins Darwinism
  (E. Mayr)
• Evolution species come and go through time, and
  while they exist they change. (But the real
  bearer of evolution is the individual, not the
  species!)
• Common descent
• Species multiply the diversification of life
  involves populations of one species diverging
  until they become separate species
• Gradualism evolutionary change occurs through
  incremental small steps new species are not
  created suddenly.
• Natural selection some variants change
  individuals survival reproduction probability.
• Against Lyell species are not stable not
  perfectly adapted to environment species are not
  created quickly (Lyell was a theory of species
  sequence, not of species evolution!)
• Against Lamarck individual changes are not
  inherited common descent

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• 4.3 Darwins Speculations about the biological
  fundament
• Notabene Darwin had no idea about the place and
  nature of genetic information, laws of
  inheritance (Mendels rules etc.)
• Theory of Pangenesis all cells produce little
  gemmulae (little buds), they gather in
  reproduction organs. In the young they mix
• a Lamarckist remainder in Darwin!
• Still even in 1868 (book on selective breeding of
  animals and plants). Soft inheritance, acquired
  traits are passed on.

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• 4.4 Some open questions in Darwin
• Small steps or jumps? (Is mutation or selection
  the more important driving force of evolution?)
• Why sudden speeding up of evolutionary change,
  rapid growth of species numbers in certain stages
  of earth history (Cambrian explosion etc.)
• No real theory about inheritance, similarity and
  variability
• Why is there life at all? No procreation (no
  conflict with Pasteur 1859) maybe 4 or 5
  original forms of life. Reference to creator more
  courtesy?
• Speculation about the warm little pond (letter to
  Hooker 1871)
• But if (and Oh! What a big if!) we could
  conceive in some warm little pond, with all sorts
  of ammonia and phosphoric salts, light, heat,
  electricity etc, present, that a protein compound
  was chemically formed ready to undergo still more
  complex changes...
• Similarity to Miller-Urey experiment 1953,
  primordial soup

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The Miller-Urey experiment
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• 4.5 Ernst Haeckel (1834-1919) Materialism with
  idealist traces
• Great graphic illustrator, popularizer in Germany
• Materialist (Darwinism as anti-religious and
  anti-conservative program!)
• Yet some idealist remainders, idea of dynamics
  of growing complexity
• takes on recapitulation-idea of Kielmeyer
• Creates terms, and biogenetic fundamental law
  ontogeny repeats phylogeny
• Evolutionary morphology similarity of gastrula
  stage? speculation to a Gastrea as common
  ancestor
• ? tree of life
  suggests height
• of development,
  dynamics to complexity.
  (false successful simple
  organisms,
  backward-developments)

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• 4.6 Francis Galton (1822-1911) Evolution becomes
  statistical
• Cousin of Darwin, multidisciplinary scientist
  statistics, fingerprints, efficacy of prayer,
  questionnaire, blood-transfusion, eugenics
• Experiments against Darwins gemmulae
• semi-lamarckian speculative theory of inheritance
• Important Separation Organism genetic
  information (stirp). Organism is just a
  representative selection from stirp, like a
  parliament
• Inheritance becomes statistical matter, every
  parent contributes ½
• Variation is now a matter of the population (not
  the organism, not the species!). New subject of
  evolution. Farewell to Aristotelian ideas.
• Beginning of theoretical biology as a
  mathematicised discipline!

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• 4.7 August Weismann (1834-1914) The organism as
  mere vehicle of genetic information
• Radical materialist
• Similar to Galton, but with more empirical
  justification experiments with sea urchins
  (ježinac) germ cells are separated from the rest
  of the organism in very early stage
• ? Separation germ cells somatic cells
• Half-speculative theory of immortal germ
  plasm.
• Revolutionary genetic info isthe bearer of
  variation, notthe organism only vehicle
• Separation growth/reproduct.
• Lamarck finally dead
• Cf. Dawkins Selfish Gene !!

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• 4.8 Gregor Mendel (1822-1884) The first robust
  theory of inheritance
• OSA monk and abbot in Brno (CZ). Experiments with
  peas etc., publication 1865 in Austrian Journal,
  no reception. Only from 1900!
• Question in those times Does evolution go
  uniformly or in jumps?
• Darwin (Newtons ideal! Natura non facit
  saltus!) uniformly
• Huxley, Galton undirected, small mutations /
  variations
• BUT such undirected small changes can cause no
  big changes, since statistics equalizes their
  effect. Statistical samples tend to average.
• Hence, there must be other factors, Mutation must
  be more important.
• Mendels method reduction to only few (Y/N, not
  gradual) features, quantification (counting)
• Experiments with crossing of peas and beans
  features white/lilac flowers white/red/pink
  flowers, smooth/wrinkled seed.
• Result Mendels rules

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• 4.8 Gregor Mendel (1822-1884) The first robust
  theory of inheritance
• Mendels first law ( some more)
• Presumptions unmixable, discrete factors of
  inheritance
• mutation more important than selection,
  bigger jumps are possible
• But biometry, statistics show continuous slow
  change. How can this
• possibly be harmonized? Great crisis of
  Darwinism in early 20th century!

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• 4.9 The Molecular Revolution in Evolutionary
  Biology
• End of 19th century discovery of chromosomes in
  cell nucleus
• 1903/04 Sutton/Boveri genetic info stored in
  chromosomes
• 1910 Johannsen Terminology Genotype (inner
  constitution, info)
• Phenotype (appearance)
• Genotype ? Phenotype!
• The genotype is inherited, not directly
  the features!!
• After 1909 Drosophila experiments (quick
  reproduction, only 4x2 chromos.)
• Beginning of localisation of genetic info on
  chromosomes (chemistry still unknown till 1953!)
• Insights - some features controlled by more
  than one gene
• - there are interactions between genes
• - one gene can influence more than one feature
• HENCE 11-matching genes ? features false
  since early 20th century!
• genetic blueprint metaphor likewise wrong
  (still it is around)

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• 4.9 The Molecular Revolution in Evolutionary
  Biology
• 1953 Watson/Crick Discovery of double-helix
  structure of desoxyribonucleic acid (DNA)
• Since mid-1960 Mechanisms of gene expression
  (DNA RNA proteine synthesis) begin to be
  clarified
• Human genome project 1990-2003
• Mind the correct way of speaking
• Sequencing the genome.
• (Not decoding the genetic code
• fallback to blueprint model!)

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• 4.10 The Modern Synthesis (1920s, 1930s
  onwards)
• Darwinism had no undisturbed victorious career
  no uniform development of post-Darwinist biology.
  Especially Mendels genetic discoveries caused
  worries quick changes, either/or are possible.
  Mutation is more important!
• Darwins intuition small, incremental steps,
  selection is more important
• The great crisis of Darwinism / Eclipse of
  Darwinism (J.Huxley 1942)
• Late 19th/ early 20th century all 5 tenets of
  Darwin come under doubt, many biologists step
  back to older theories, partly speculative.
• Extension of population genetics (Ronald Fisher,
  Sewall Wright, John B. S. Haldane) Complex
  mathematical models to combine Mendel Darwin
• Some ideas from population genetics
• On genotype level Mendelian jumps, on phenotype
  level only small Darwinian changes since
  features often depend on many genes!
• Population (not individuals) as the unit of
  evolution, statistics equalize in some
  individuals Mendelian jumps, in population slow
  Darwinian shift
• The smaller a population, the easier are big
  jumps possible.

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• 4.10 The Modern Synthesis
• Theodosius Dobzhansky, Ernst Mayr and others
• The Modern Synthesis, Synthetic Biology of
  Evolution
• connects Darwinian core idea (stepwise
  evolution, selection)
• Mendelian genetics
• Population genetics
• Biometry
• Microbiology
• Biochemistry
• Behavioral science
• Paleontology
• Geology
• etc.

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• 4.11 Some special ingredients of the Modern
  Synthesis
• Genetic drift / bottleneck / founder effect
• (A non-adaptive effect, against
  pan-selectionism!)
• Punctuated equilibrium (Eldredge/Gould)
• Various explanations of stages of stasis
• and rapid evolutionary change allopatric
• origin of species (related with genetic drift)
• Neutralism (Kimura) many big changes in DNA come
  and go,
• without being tested by selection, neutral
  changes possible

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• 4.11 Some special ingredients of the Modern
  Synthesis
• Cooperation between genes Regulator genes,
  governing the expression of other genes, genetic
  switches. E.g. Hox genes, regulate development
  of legs, antennas etc.? mutations in such genes
  may have big effects!
• ? Evo-Devo (Evolutionary developmental
  biology)
• similarities in the genotype are astonishingly
  high across species, but
• phenotypes differ dramatically!
• Hence genes in themselves are not so important
• Hence difference must lie in the expression of
  the genes, development of the organism, regulator
  genes etc.
• Evolutionary biology in the past took adult
  organism (and populations out of them) as subject
  to natural selection,
• EvoDevo takes the whole process/cycle of
  development of an organism as the subject of
  natural selection.

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• 5. Evolution Theory-structures and concepts
• 5.1 Theory-structure of EB
• Physics, chemistry etc. law-like explanations,
  able to prediction
• false predictions a part of falsification
• Evolutionary biology admits of (almost) no
  interesting predictions
• Herschel un-scientific, mere statistical
  relations
• (young) Popper unfalsifiable tenets like the
  survival of the fittest, circular.
• Partial answer
• (1) Parts of explanations admit of predictions
  (cell level etc.)
• Some few experiments with bacteria admit of
  prediction even of direction of evolution on
  macro-level in lactose solution, bacteria with
  mutation develop genes to process lactose
• (2) Why decreeing that all scientific
  explanation must resemble physics?

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• 5.2 Is EB a science?
• Not a science like physics combination of
  natural historical disc.
• Rather a scientific research program, uniting
  many disciplines
• Criteria by Philip Kitcher (The Advancement of
  Science, 1993)
• A scientific practice
• Investigates an accepted domain of objects
• Investigates accepted problems and questions
• Has a non-natural technical terminology
• Has commonly shared convictions at its basis
• Applies accepted means and methods
• Has accepted standards on aim and success of the
  investigations
• Has accepted standards how to accepts results
  from other sciences
• Is part of a social network
• Evolution biology scores excellently under most
  criteria!

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• 5.3 The bearers / objects of evolution
• Individuals / organisms?
• Species?
• Populations?
• Genetic information?
• Life-cycles? ?different metaphysical views
  on objects of biology!
• 5.4 What are the traits / characteristics /
  features tested by evolution?
• a) only bodily features (shape, food
  tolerances, ) or also behavior? Dawkins
  the extended phenotype (including behavior) is
  being tested!
• b) Adaptive traits (with a success story)
  maladaptive traits by-products
• c) Is every feature adaptive? ? Panselectionism.
  (But what is a feature??)
• d) Beware of a frequent misunderstanding
  concerning success story of trait - not
  the trait makes its success story (the trait is
  not there from beginning!) - rather ex
  post, we see a success story of the trait and its
  previous traits (evolution does
  bricolage with available traits!). No trait
  essentialism

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• 5.5 Misunderstandings
• Survival of the fittest - Can be incremental
  need not be perfect
• - need not be the strongest/biggest/
• Struggle for life - is not intra-population
  struggle
• - need not be fight with similar species
• - just general struggle with the ecological
  conditions food, climate, safety,
  nesting-places
• 5.6 Genes ( an unsettled debate! by the
  genes is no explanation!)
• place on the chromosome? surely to imprecise
• sequence on the DNA (concrete gene)? things
  are more complicated are regulated
  /switched-on genes really genes?
  Coding/non-coding DNA? Some DNA sequences are
  read more than once, some corres-pond to more
  than one proteine? Beginning/end sometimes
  unclear,
• whatever makes a difference in fitness
  (abstract, functional gene)? may come close to
  antirealism concerning gene genetic info.

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• 6. Evolution between science and world-view
• 6.1 Overview
• SCIENCE
• Darwins (historical) Darwinism
• Darwinism Synthetic theory of Evolution (1940
  onwards)
• Current EB (New synthesis, EvoDevo, )
• CONTROVERSIAL
• Pan-Selectionism
• Sociobiology
• Cultural Evolution, Memetics
• NON-SCIENCE
• Social Darwinism
• Pop-Darwinist Slogans

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• 6.2 Pan-Selectionism
• Sometimes also strict neo-Darwinism,
  Darwinist orthodoxy
• (Terminology seems not to be entirely fixed)
• Thesis natural selection is the driving force of
  evolution every feature has an evolutionary
  success story behind it
• Tendency to a deterministic account of the world
  and the human being evolutionary successful
  features are /- hard-wired, that includes also
  our mind, our reactions, etc.
• Critical evaluation empirically unplausible in
  the light of modern genetics
• Ironically a remainder of old perfect
  adaptation ideas (natural theology)

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• 6.3 Sociobiology
• Extension of evolutionary explanations also to
  our behavior, moral beliefs etc.
• First visions already in Darwin moral tribes
  might be more successful
• Example1 why is altruism evolutionary
  successful?
• At first glimpse not at all. Risk your life,
  lose eating-time etc.
• Example whistle-blowing birds
• But kin-selection / group-selection (E.O. Wilson,
  Sociobiology 1975) brothers/sisters have 50
  same genetic info, cousins 25, ? saving the
  life of, e.g., 5 cousins by whistle-blowing (and
  sacrifying own life!) increases the survival of
  own genetic info! 125 - 100 25
• Example 2 why are moral norms evolutionary
  useful?An economic way to secure cooperation of
  group members, internal/mental control instead of
  expensive external forces
• Critical evaluation Empirically unclear
  evidence
• Manifold cultural shapings of behavior, limit
  natural/cultural unclear
• Sociobiol. is no exclusive explanation (altruism
  is nothing but xy)

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• 6.4 Cultural evolution, memetics
• 1976 Richard Dawkins, The Selfish Gene (and in
  later books)
• 1995 Daniel Dennett, Darwins Dangerous Idea
• Basic idea behavioral and cultural practices are
  passed on by imitation, they can be seen as items
  of cultural information memes. Such memes
  undergo competition and selection, some do
  propagate, some do not
• Examples termite-poking of chimpanzee tribes
  language, use of fire, wheel, wall-graffiti,
  literary figures, cooking recipes, religion,
  product designs, business ideas
• Critical evaluation Suggestive examples
• But huge differences between genes and memes-
  genes mutate at random, memes often
  intentionally- genes from distant branches of
  evolution non mixable, memes are- memes are
  inherited in Lamarckist ways, individual
  inventionsIn sum misleading metaphor,
  parasitic on good image of biology. Even
  dangerous when mixed with ideas of neo-liberalism

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• 6.5 Social Darwinism
• Label from 19th century, roots rather in Thomas
  Malthus and Herbert Spencer than in Darwin.
• Basic ideas (1) Evolutionary explains (and
  predicts) social facts (2) Evolutionary biology
  is not only descriptive (what is
  the case?), but also normative (what should
  we do?)
• (3) Evolution is progress
• (4) There are good and bad genetic
  information-bits (for that progress!)
• (5) Progress should not be retarded, bad
  genetic info should be suppressed
  (handicapped, lower races, )
• Usually rivalry of all against all (people in a
  society, nations / nations, ), misunderstanding
  of struggle for life
• Notabene NS ideology was not closely connected
  with Darwin. Racism!

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• 6.5 Social Darwinism
• Critical evaluation
• (1) Is/ought fallacy, description / normativity
  fallacy / genetic fallacy
• (2) Biological basisof Social Darwinism is
  dubious and rather Lamarckist Evolution is
  progress. But progress/regress are not
  biological categories at all
• (3) It depends on the environment which forms are
  progressive / more successful (small and
  undemanding animals might be most
  successful!)I.e., social Darwinism rests on some
  aesthetic ideals of what is healthy, strong,
  progressive etc.
• (4) Even if we could create a perfect natural
  world, this does not guarantee a pleasant,
  humane culture. False genetic determinism, nature
  does not determine culture.

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• 6.6 Some pop-Darwinist slogans
• Nature and Evolution are nothing else but a
  huge process of chance and random
• BIOLOGICALLY FALSE, at least selection is not
  random.
• Darwinism means that mutation and natural
  selection explain every feature.
• BIOLOGICALLY MOST PROBABLY FALSE, only most
  narrow-minded pan-selectionists would deny other
  evolutionary effects
• Cosmic evolution There is one big
  evolutionary process from Big Bang to human
  culture.
• CONCEPTUAL NONSENSE. (1) Not every
  agglomeration and development process (as in the
  early universe) is also an evolution process.
  There is no multiplication, mutation,
  inheritance, and selection for protons, galaxies,
  stars etc. Over-extension of a biological
  metaphor. (2) On cultural evolution, see 6.4.
• 
  
  

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• 6.6 Some pop-Darwinist slogans
• Society and economy work according to
  evolutionary laws.
• SEE 6.4 above!
• Science (like biology) consists of falsifiable
  claims only, world-views are irrational and
  subjective.
• FALSE FROM THE VIEWPOINT OF PHIL. OF SCIENCE.
  (1) Too narrow concept of science
• (2) Background assumptions are even at work in
  the sciences see Kuhns paradigms, Lakatos
  hard cores of research programs. Border to
  world-views fuzzy world-views contain rational
  structures, can be more/less plausible, and
  rationally discussable. See Popper there are
  genuine philosophical problems, beyond science.

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• 6.7 Biology and Religion On Creationism,
  Intelligent Design etc.
• A bit of history
• USA a country of small religious groups, partly
  literal reading of the Bible
• About one half of the population has serious
  doubts about evolution
• Empirical fundament unclear spots in evolution,
  cosmic fine tuning
• Spectrum
• Short-time (Young-earth) creationism 6
  days, about 6000 yrs ago
• Long-time creationism (special creationism)
  successive intervention
• Intelligent Design design-plans, to solve
  irreducible complexity
• Theistic Evolution (Vatican II God as 1st
  cause carries 2nd causes)
• Deism
• Atheism, metaphysical naturalism
• Wealthy think-tanks, www.discovery.org etc.,
  disinformation, wedge

57

• 6.7 Biology and Religion On Creationism,
  Intelligent Design etc.
• Objections to ID
• Unclear ontology of design plan, at odds with
  usual scientific ontology
• Selective evidence, focused on explanatory gaps
  and failures of EB
• Some irreducible complexities are reducible
  regulator-genes etc. may explain complexities
• Filling-the-gap-theology every new biological
  discovery makes God more irrelevant, theology on
  constant retreat
• ID proves only world-constructor (demiurg), not
  creator
• Why a single God behind the 1000s of appearances
  of ID? Tacit background theology smuggled in.
• Problem of evil radicalized source of bad
  design, senseless design?
• In sum neither necessary nor fruitful for the
  Christian.
• (Due!) criticism of reductionism and ideology
  should not turn into (undue) pseudo-scientific
  blends of theology and biology.

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• 7. Summary
• Aristotle inaugurated a vision of biology with
  the species in focus, and a teleological view at
  the world yet, without external design.
• The raise of modern evolutionary thought began
  before Darwin and was based on empirical findings
  as well as on speculative ideas. Darwin and
  Wallace developed the first coherent, large-scope
  theory with a broad empirical basis (still with
  many blind spots).
• The basic ideas of Darwin are still topical in
  the core of current EB. However, EB cant be
  reduced to mutation and selection.
• Current EB is a research program with many open
  questions, especially about the impact of natural
  selection. Central concepts like gene admit of
  different readings.
• This is one reason why EB has a strong affinity
  to be reduced to an ideology, more than other
  sciences. Another reason is the wide scope of EB,
  from the explanation of shape to behavior.
• ID is a dubious blend of theology and biology
  which appears neither necessary nor useful for
  the theologian.

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• 8. Repetition questions
• How does Aristotles conception of science differ
  from Platos?
• Name 4 of Aristotles biological writings and
  their (rough) content.
• How does Aristotles method in biology
  resemble/differ from today?
• What type of discipline is an episteme, what a
  historia?
• Why did we describe Aristotles biology as
  teleology without design?
• Sketch Empedocless explanation of the origins of
  life and Aristotles counter-argument.
• Aristotles doctrine of the stability of species
  (what is it?) is said to have prevented
  evolutionary ideas for centuries. But are there
  any traces of variability of species in
  Aristotle?
• How did Aristotle describe the development of an
  embryo?
• What is preformationism?
• What is procreationism?
• What was new about Linnés taxonomy system? What
  are its limits? Was he an Aristotelian?

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• What other inventions did he make which are still
  important for biology?
• Sketch Buffons anti-Linnéan position.
• What was the Paris Academy Dispute 1831
  ultimately about? (Dont just say idealist
  versus evolutionary morphology, but explain the
  issue!)
• What are homologous organs, what are
  analogous ones?
• Explain some of the basic intuitions of
  Romanticist biologists, and name some important
  persons.
• Why can we say that Lamarck presented the first
  evolution theory? Only under what conditions
  should something be called an evolution theory?
• What does crucially distinguish Lamarckism from
  standard evolutionary biology?
• How did Lamarck explain the change of organisms
  in the course of time?
• Name some thinkers and researchers who influenced
  Darwin!
• How did Malthus change Darwins thought?
• Why is Darwins theory of natural selection no
  theory of perfect adaptation?
• What is sympatric, what allopatric origin of new
  species?
• How did Ernst Mayr summarize classical Darwinism?

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• Sketch Darwins gemmulae theory. What was it
  good for, what was it supposed to explain?
• List some open problems in Darwin.
• Why are Haeckels tree-diagrams suggestive in a
  false direction?
• What does his biogenetic fundamental law say?
• Describe the separation of genetic information
  from the organism in Galton, Weismann and
  Dawkins. In what are stirp, germ plasm and
  selfish gene similar?
• What new point of view dis Galton bring into
  biology? Why does this bring a turn away from
  Aristotelian ideas?
• Why was the Weismann barrier seen as a
  death-blow to Lamarckism?
• Why did Mendels discoveries shake the Darwinism
  of his time? What was the worrisome problem?
• Sketch some main steps in the discovery of
  genetic information.
• Why is we can today decode the genetic code a
  problematic way of speaking?
• Why can population genetics perhaps unite
  Darwinist and Mendelian ideas?
• What does pan-selectionism claim?

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• Why is the (empirically backed!) idea of genetic
  drift an argument against pan-selectionism?
• Try to describe some basic ideas of EvoDevo. Why
  is EvoDevo a remedy against the misconception of
  a genetic blueprint?
• How do evolutionary explanations differ from
  physical explanations?
• Why has evolutionary biology a special structure,
  different from other natural sciences?
• What units/bearers of evolution were proposed in
  the history of biology?
• Why is it misguided to say feature F had an
  evolutionary success story?
• What did Darwin mean by struggle for life?
• Sketch different notions of a gene.
• How would socio-biologists explain that altruism
  is sometimes evolutionary successful, even if it
  goes to sacrificing ones life?
• What is a meme? Why is cultural evolution a
  non-starter?
• Describe the mistakes of Social Darwinism.
• Why is Intelligent Design not a wise choice for
  theologians?
•  
• GOOD LUCK FOR THE EXAM!