Early Evolutionary Thoughts

Transcription

1 Early Evolutionary Thoughts

2 Anaximander ( BC) Earth was first in a liquid state Humans evolved from fishlike creatures who left the water

3 Empedocles (400 s BC) Humans and animals arose as various body parts joined together randomly Some unable to reproduce, become extinct, others thrived (natural selection??)

4 Hippocrates ( B.C.) the inheritance of acquired characters - habits or characteristics of the parent will be passed to the offspring principle of use and disuse - a part that is used will become more elaborate and a part that is not used will be lost. Variation was due to differences in environments and habits

5 Plato ( BC) Plato also introduced the idea of an animate or living cosmos - all physical and living systems are linked together into a harmonious whole a supernatural harmony that could only be understood through pure thought The Platonic system replaced naturalistic explanations.

6 Thoughts on Evolution Universe had general laws that could be discerned through pure thought and be described. Plato developed many ideas about the nature of the universe. One that was very influential and still survives in some form today is ESSENTIALISM or IDEALISM. The form of an object or organism is an outward expression of its essence an unseen underlying truth about the nature of an object Plato thought that underlying every object s existence was its essence, or essential nature. The variation among types of an object or types of organisms was an error, or just various degrees of imperfection from the true essential nature.

7 Aristotle ( BC) Species unchanging ideal form Successful creatures perfecting principle Variation is noise

8 Scala Naturae Fixed species Hierarchical scale Perfecting principle Variation - noise

9 Lucretius (94 55 BC) Wrote about:... the preservation of animal life in accordance with the law of the survival of the fittest

10 Important ideas prevail from the ancients Fixed unchanging Species Scala Naturae (simple complex) Perfecting principle Variation is not important

11 Christian Philosophy God as Creator ex nihilo Static world: no extinction; no change in species Humans unique Michelangelo, Sistine Chapel Ceiling... Creation of Adam

12 Static, divinely ordered world Predominant way of thinking not only in religion and philosophy but also in science

13 Natural Theology Nature of God understood by reference to His creation natural world Inspired naturalists to look at form in the context of function Groundwork for evolutionary studies of adaptation and fitness

14 John Ray ( ) Father of Natural History in Britain Searched for the natural system classification of organisms reflecting Divine Order of creation

15 Carolus Linnaeus ( ) Binomial Nomenclature Genus species To discover order in the diversity of life for the greater glory of God

16 William Paley ( ) The metaphor of the watchmaker

17 ... when we come to inspect the watch, we perceive... that its several parts are framed and put together for a purpose, e.g. that they are so formed and adjusted as to produce motion, and that motion so regulated as to point out the hour of the day; that if the different parts had been differently shaped from what they are, or placed after any other manner or in any other order than that in which they are placed,

18 either no motion at all would have been carried on in the machine, or none which would have answered the use that is now served by it the inference we think is inevitable, that the watch must have had a maker -- that there must have existed, at some time and at some place or other, an artificer or artificers who formed it for the purpose which we find it actually to answer, who comprehended its construction and designed its use.

19 Living organisms, are even more complicated than watches, "in a degree which exceeds all computation." How else to account for the often amazing adaptations of animals and plants? Only an intelligent Designer could have created them, just as only an intelligent watchmaker can make a watch: Only an intelligent Designer could have created them, just as only an intelligent watchmaker can make a watch: That designer must have been a person. That person is GOD.

20 Challenges to Established Views Astronomy Global Exploration

21 Challenges to Established Views Astronomy Nicholas Copernicus ( ) Heliocentric Model

22 Challenges to Established Views Global Exploration New areas -- new information Plants and animals never seen before

23 Challenges to Established Views Geology Existence of Fossils Species extinction Age of Earth Biological Transformism Extinction

24 Challenges to Established Views Extinct species? Where did they come from? Why did they die out? Geology Fossils

25 Challenges to Established Views Geology 1st scientific challenge to static world Geological processes constant Earth very old James Hutton ( )

26 Age of the Earth Irish Prelate & Biblical Scholar Creation on 22 Oct 4004 BC at 9:00 AM James Ussher ( )

27 Challenges to Established Views Biological Colleague of Lamarck at the National Museum of Natural History in Paris Expert in Comparative Anatomy Georges Cuvier ( )

28 Cuvier on the Fossil Record Elephant and Mammoth bones greatly differ, therefore represent different species Mammoth bones represent a species that is now extinct

29 Cuvier on the Correlation of Parts and the possibility of transformism

30 Interpretation of the Correlation of Parts Transformism is impossible because it would require a reintegration of many parts. A change in any one part in isolation would be disastrous to the individual. So: Extinction is possible but Transformation of one species into another is not

31 Theory of Catastrophism History of the Earth largely static but punctuated by major extinction events (later termed catastrophism) The Earth must be older than scriptures suggest Georges Cuvier ( )

32 Support for Cuvier?

33 Challenges to Established Views Geology Natural laws constant in time & space Events of the past explained by processes observed today Geological changes occur slowly and gradually not as catastrophes Lyell ( ) Theory of Uniformitarianism

34 Challenges to Established Views Biological Charles Darwin s Grandfather Formulated one of the early theories of evolution But no mechanism Erasmus Darwin - ( )

35 Challenges to Established Views Biological Colleague of Cuvier at the National Museum of Natural History in Paris Expert in Invertebrate Zoology Provides a Coherent Mechanism of Transformism Jean-Baptiste de Lamarck ( )

36 Lamarck on Transformism (Philosophie zoologique) Origin of living beings through spontaneous generation Organisms have an inner drive ( besoin ) that causes them to rise up the Chain Of Being. Man is at the top of the Earthly chain. Dynamism for this ascent of life over time supplied by caloric and electricity Vitalistic interpretation of transformism Principle axis of Lamarckian transformation is that of linear series

37 A Lamarckian View of Transformism Lamarckian transformation: a linear series of modified forms over time Species change, but no new species are formed

38 Lamarck on Transformism (Philosophie zoologique) 1. Transformation caused by the interaction of organisms with their environments 2. The environment is a hostile force that interferes with the ascent to the top of the Chain of Being. 3. This interaction causes variability within a type

39 Lamarck on Transformism (Philosophie zoologique) "First Law : use or disuse causes structures to enlarge or shrink "Second Law : all such changes were heritable

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41 Jean-Baptiste de Lamarck Incorrect Assumptions Theory teleological (goal directed) Characteristics acquired during life of organism passed on to their offspring

42 Lamarckian Views of Extinction and the Fossil Record Extinctions do not occur Organisms have high reproductive potential (Intrinsic Growth Rate) Fossils represent organisms that have become a higher form As organisms ascend the Chain of Being they are replaced by spontaneous generation of lower life forms

43 Is Lamarckism dead?

44 What is CASS? CRISPR-Cas, where CRISPR stands for Clustered Regularly Interspaced Short Palindromic Repeats and Cas for CRISPRassociated genes (sometimes referred to as CASS or simply CRISPR system)

45 Unconvinced? Norrbotten, northern Sweden. A remote location with population density of 5/sq mile. Church kept detailed records of events including marriages and birth. Lars Olov Bygren (Umeå University, Sweden) did a longitudinal study. 1800, 1812, 1821, 1836 and crops failed. paternal grandfather's food supply was only linked to the mortality risk ratio of grandsons. paternal grandmother's food supply was only associated with the granddaughters' mortality risk ratio. European Journal of Human Genetics (2006) 14,

46 The Poem And in the ages after monsters died, Perforce there perished many a stock, unable By propagation to forge a progeny. For whatsoever creatures thou beholdest Breathing the breath of life, the same have been Even from their earliest age preserved alive By cunning, or by valour, or at least By speed of foot or wing. And many a stock Remaineth yet, because of use to man... Lucretius. On The Nature of Things, Book V