Week 1 Flashcards
who are the four main influential authors of evolutionary theory?
- Jean Baptiste de Lamarck (1744-1829)
who wrote the first theory of evolution
called the Lamarckian theory of the
transmutation of species. - Charles Darwin (1808-1882)
famous HML Beagle voyage, Gallipolis
finch samples, wrote the origin of
species with Wallace which included the
three elements of evolution (competition,
variation and inheritance), wrote the
decent of man in 1871. - Thomas Robert Malthus (1766-1834)
wrote the Malthusian theory of evolution
with four key elements: production of
food, population size, Malthusian
catastrophe and positive checks. - Alfred Russell Wallace (1823-1913)
took heaps of specimen samples, wrote
the Wallace and Webber lines theory,
Sarawak law, ternate, co-wrote the origin
of species.
who wrote the first evolutionary theory? what was the theory?
Jean Baptiste de Lamarck (1744-1829)
Before Jean Baptiste de Lamarck people
believed that animals satyed in the same
form they were created in.
Jean wrote the first scientific theory of
evolution.
The Lamarckian Theory of Evolution
(transmutation of species) poists that
increasing complexity in nature is due to
animals adapting to their local conditions
through use and disuse. Meaning that
physical changes in an organism coincide
with uses and disuse of said features to aid
in their survical and are passed down onto
offspring.
E.g., the girraffe grew long necks due to
their repeated extension of their necks to
reach higher leaves.
Critqued for its inability to explain what
happens when animals loose limbs and
that deformity is not passed down onto
offspring.
what is the Malthusian theory?
Wrote the principle of population which proposed his theory that food production progresses linearly over time.
The population expands quadratically (i.e., much more quickly).
When population exceeds the production of food that is currently available this is called the Malthusian catastrophe.
To address this positive checks such as war or famine occur to bring down population size to meet the current rate of food production.
when was the species of origins by Darwin & Wallace written?
1859
(11) people who Influenced Charles Darwin?
a. Robert Edmond Grant
b. John Edmonstone
c. William Paley
d. Alexander Von Humboldt
e. William Herschel (1831)
f. John Steven Hanslo
g. Captin Fitzroy and Charles Lyell
h. John Gould
i. Emma Darwin
j. Thomas Robert Malthus (1766-1834)
k. Anonymous (1884)
(1) who is Robert Edmond Grant?
Darwin fell under the wing of Mr Grant who taught him about Lamarkians theory of evolution (transmutation of species).
(2) who is John Edmonstone?
Freed slave from South America which taught him all about species diversity outside of England and taxidermy.
(3) who is William Paley?
When medical school didn’t work for Darwin he was sent to Cambridge to become a priest.
There he learnt about William Paley’s work on “Natural Theology” and he is often referred to as the grandfather of intelligent design.
He is also famous for the watchmaker analogy “if you found a watch in the sand, it would be so irrefutably complex to be explained by nature that you must conclude that someone made it even if you don’t know who the watch maker is”
(4) who is Alexander Von Humboldt?
Famous for his electric eels work where he wrote very detailed descriptions of how things work in nature.
The first step at adopting a meticulous scientifc approach with detailed accounts that are still used today.
Combines a passion for nature and science.
Unity of nature: Nature herself is sublimley eloquent. The stars as they sparkle in finament fill us with delight amd ecstacy, and yet they all move in orbit with mathematical precision.
(5) who is William Herschel (1831)?
The perliminary discourse on the study of natural philosophy
Presented the idea that there are irrmutable laws in nature to be discovered and these laws govern natural processes.
(6) who is John Steven Hanslo?
Biology classes on Botany.
Plants, herbiums, and variation withina fixed species.
Recommended Darwin for the HMS Beagle Vouage
(7) who are Captin Fitzroy and Charles Lyell?
Fitzroy took him on the HMS Beagle vouage around the world and gave him a book by Charles Lyell called the principles of geology which argued that the earth is much older than we once thought and has gradually changed overtime by the laws of nature. They believed humans to be an expection to this and perceived to be unchanging in a changing world.
On the vouage he had contact with slavery.
Took samples from lots of places but didn’t adequatley lable when and where they came from.
His focus was more on geology rather than biology at this stage.
(4) Gallapogise Island bird samples were taken and sent hoe to John Gould for analysis.
(8) who is John Gould?
Told drawin he had more varitation than (4) species in his samples all taken from the same small island. Why? What is the purpose of having so much variation in species in the same ecological location? This is a question he had not answered yet.
However, now we know that variation within finchs occurs because it allows them to fufill ecological niches.
Following Darwins return home he reflected on how he was only well known as a geologist and not a biologist. Thus, he took the time to bolster his credentials and conduct research and papers on biology; particularly on what molosces are and their variations using the Lamarckian theory of transmutation.
He wasn’t able to address “why” variation occurs till he read Malthus’s theory of evolution.
(9) who is Emma Darwin?
Darwin married his cousin. She was highly religous and feared that her husbands beliefs in tramsmutation of species (which went against christian beliefs) would seperate them in the afterlife.
(10) who is Thomas Robert Malthus?
Wrote the principle of population which proposed his theory that food production progresses linearly overtime. The population expands quadratically (i.e., much more quickly). When population exceeds the production of food that is currently available this is called the malthusian catastrophe. To address this positive checks such as war or famine occur to bring down population size to meet the current rate of food production.
This theory guided and provided insights to his systematic enquiry of plants and animals which lead to the realisation that overtime favourable variations tend to be preserved and unfavourable variations die out. He begun to see that variation allowed species to adapt to changes in their natural environment which increased their survivial and chances that their variation is preserved and passed onto their offspring.
At this point darwin is documenting his ideas but he doesn’t publish anything
(11) who is Anonymous (1884)?
The publication of “the vestiges of the natural history of creation” written by an anonymous author.
It was a very popular paper which the king read as a bedtime story to his wife. It was highly speculative and not scientific at all.
It focused on evolution of all things being a linear process with english males being the pinical of the tree which we know today is not true.
Fish (F), Reptiles (R), and Birds (B) were believed to be branches of evolution which form the path to mammals.
This publication lead Darwin to be apprihensive on publishing his own work.
what (3) people influenced Wallace?
He was influenced by the same major authors of their time as Darwin with these (3) additions:
Ida Laura Pfeiffer
Wallace’s teaching job meant he had access to literature by Ida Laura Pfefiffer who was a naturalist.
This meant he has also was exposed to the same theories as Darwin was.
Henry Walter Bates
Was a collegue of Wallace’s who together got very interested in studying variation in beetles.
Anonymous (1884)
Wallace also read “the vestiges of the natural history of creation” instead wallace and his brothers reaction differed from Darwin in that instead of being scared to publish work on the subject they were inspired to test the proposed theory.
E.g., he syayed that he would like to study the varitation of beetles
How did the Origin of species come about?
Darwin and Wallace worked independently on developing a theory of evolution.
Wallace sent his “ternate” to Darwin to review and pass on to Charles Lyell to publish. It was lost. Darwin and Wallace ended up coming up with a very similar theory. they came to a gentleman’s agreement to collate their work and copublish the origin of species.
Queen Victoria’s reign was between — and —
1819-1901
what were the three key changes that occurred over queen victoria’s reign?
o Industrialisation and Urbanisation
o Reform Acts (extension of the franchise)
1832, 1867, 1884
o Empire, Travel, & Technology
What are (4) examples of industrialization and urbanization of England over the 19th century?
a) Population Change of England:
• Over the 19th century the population of
England trippled from apporx. 10 million to
30 million people.
• The rapid population growth corresponded
with the rapid Urbanisation of England.
b) Population Change of London:
• From 1856 when Darwin published his
paper called “the origins of species” the
popuation of England doubled from 2
million to 4 million people in London.
• London is the largest city of England which
was industrialied and a large manufactuer.
c) Transition from Rural into Urban:
• The percentage of rural areas of England
decreased overtime and the percentage of
urban cities increased between 1801-1881.
d) Elizabeth Barret Browning (1806-1861)
• An english author who wrote the famous
poem “the cry of the children” in 1843.
• This poem was designed to pull on the
heart strings and compare innocent fawn
playing in nature with the children in the
land of the free where the transistion from
rural into urban areas lead to issues such
as child labour.
• They critque the current sociocultural
context which forces children to work in
mines, and wish about death instead of
playing in nature and being happy and free
like they should be; critiques the
romantisization of industrialisation and the
immorality of child labour
What are (3) examples of Reform Acts (extension of the franchise) that occurred over queen victorias reign?
a) Redistribution of wealth and power from
aristocracy to emerging
middle/professional class.
• The economy being centered around trade
caused power to be redistributed within
society.
b) Professionalism and self-making (for men);
domesisity and virtue (for women).
• The influence of victorian gender norms
where the male went out into the world to
work and earn money and the home was
viewed as a sancturary the women took
care of (i.e., angels).
• Political change into democritisation along
with changes in societal values and norms
were slow and gradual over the 19th
century.
• “G for Gentleman” or “angel in the house”
are examples of the idealised gender norms
within victorian society in the 19th century.
c) Culture and literature responded to the
competing ideas of the desire for reform
(i.e., harnessing the industrial progress and
power) and christian rooted concerns about
harm caused and resulting problems within
society.
• Charles Dickens 1812-1870s
• A famous author in the victorian era who
addressed issue of gender norms, critiques
of industrialisation and how to respond to it.
• He viewed industrialisation as souless,
unatural and destructive.
• “brick that would have been red if the
smoke and ashes allowed it”
• “unnatural red and black like the painted
face of a savage”
• “smoke trailed themselves forever and ever
and never got uncoiled”
What are (4) exampes of Empire, Travel, & Technology changes over queen victorias reign?
a) Changing notions of space and time
• In 1898 the British Empire rapidly expanded
over the world as new territories were
established which brought war, violence,
and empowered.
• It caused people to be more aware of the
wider world outside of their home (space).
• Technological advancement shifted
peoples sense of the present (time)
• E.g., greenwich time (cities sharing the
same time), railway advancement made
travel quicker and allowed people to come
to understand their place in the world (1851-
1900s).
• The great exhibition of the works of
industry of all nations (1851) is the crystal
palace in highpark which was a grand
celerbration of the technological
advancement of man within the British
Empire. Darwin among many other famous
writers visited it.
• Thomas Hardy (1840-1928) was a writer
influenced by Darwin’s work and wrote “a
pair of blue eyes” in 1871. From his work
came the term cliffhanger where a man and
a women he was courting was walking
along the cliffside where they fell off the
edge. The man saved the women but
remained himself hanging off the cliffside.
He used this time to reflect on the geology
of the cliffside as a fossil, human
development and their impact on nature.
He says “when time collapses we are all
fossils… I’m gonna die like this fossil”.
What is Sarawak Law (Wallace, 1855) theory of evolution?
On the law which was regulated the
introduction of new species.
Proposes that new species are introduced
rather than transforming from an ancestor
overtime.
When he published this Wallace was still in
Malaysia getting closer and closer to the
origin of species.
He believed that every species has come
into existence by coincidence both in
space and time with a pre-existing closley
allied species (i.e., species are not
randomly distributed in ecological systems.
and they coincidentaly are placed next to
organisms within the same species with
variation).
What is Ternate (Wallace, 1858) theory of evolution?
This paper he wrote has since been lost
but some exerpts still remain.
“vaugely thinking over the enormous and
constant destruction which this implies, it
occured to me to ask the question, why do
some die and some live?”
Wallace got sick in Malaysia and his high
fever provided him with insight into the
meaning of life. He compared the
systematic differences between organisms
of the same species with Malfusion theory
to explain why some died and some lived.
He concluded that variation are necessary
changes for the adaption of the species to
changing conditions. Furthermore, in the
process of modification the unmodified
would die out.
In doing so, the seperation of species
could be explained.
Varities depart indefinatley from the
original type.
Three principles of Darwinian Evolution:
Three principles of Darwinian Evolution:
- Competition
- There are more individuls then the
environment can sustain (i.e., draws from
Malfusian theory). - Variation
- Individuals vary in allels/genes/traits (i.e.,
draws from Wallace and Hanslo’s work). - Inheretence
- Survival passes “something” onto their
offspring; an adaptive quality.
(3) followers of darwin?
o Thomas Henry Huxley (Darwins Bulldog)
Aithest
Heavily pushes the theory of natural
selection above creationism.
o Ernst Heinrich Philipp August Haeckel
(Darwins Dachshund)
German
Famous embryo drawings which show that
very different species often come from
very similar embryos and organism go
through individual-level evolution overtime.
At the time this was progressive scientific
thought and banned from some
universities (i.e., natural selection).
Later on he developed his own religion.
o Francis Galton (Darwins Cousin)
Psychologist who specialised in
personality.
Developed the lexical hypothesis.
Famous controversial work on “heredity
genius” and his role in the eugenics
movement (i.e., the study of how to arrange
reproduction within a human population to
increase the occurrence of heritable
characteristics regarded as desirable and
improve the human race).
who was called darwins bulldog?
Thomas Henry Huxley
who was called darwin Dachshund?
Ernst Heinrich Philipp August Haeckel
who was darwins cousin?
Francis Galton
Why was the Decent of Man (Darwin, 1871) a controversial paper?
o The Controversy:
Why do peacocks have brightly coloured
feathers? How do they survive? Darwin
came up with the theory of sexual
selection which claimed that these traits
are costly signals that help males find a
sexual partner when oppurtunities for
reproduction are smaller. Furthermore, the
costly signals help ensure that the males
with the “best” genes reproduce.
Wallace at first liked the idea of extending
their theory of evolution to mankind but
changed his mind when he became more
spiritual, adopted beliefs about dualism
and a passion for liberalisation of society.
Darwin and Wallace were not enimies;
they admired one another but were in
scientific competition.
who termed the phrase “survival of the fittest”?
what is progressionism?
Herbert Spencer
He was a progresivist who saw education
as a means to evolve humans into the
perfect being.
He termed the phrase survival of the fittest
which meant that organisms which fit into
the environment survive!
Progressionism = evolution occurs in a
stright line which is inaccurate and
reinforces heirarchy of man based on race.
what key elements did wallace and darwins original theory of evolution lack?
Understanding of the mechanisms of inheritance and geologists claims that the earth was not old enough for random variation to take place.
The resurrection of the theory of Neo-Darwinism occurred in ___ and was lead by ___
o Wallace and Darwin’s theories fell into disuse because they could not explain the key issues of inheritance and variation. o Other competing idea like “Lamarckian Theory” took its place. o The ironic resurrection of the theory as “Neo- Darwinism” by Gregor Johann Mendel (1822-1884). o He came up with two important ideas: the laws of segregation and independent assortment.
what is the law of segregation?
an organism receives 2 alleles, one from each parent that are randomly selected.
what is the law of independent assortment?
the segregation of multiple distinctive traits occur independently (R/r, A/a).
what is a homozygous pairing?
If they match i.e., RR or rr than it’s termed homozygote (dominant-dominant; recessive-recessive).
what is a heterozygous pairing?
If the mismatch i.e., Rr or rR a hybrid plant is breed and is called a heterozygote (dominant-recessive; where the dominant gene is expressed).
what are three mechanisms of selection from the Neo-Darwinism theory of evolution?
- Directional Selection:
- For example,
- Why do giraffes have long
necks?
- The juicy leaves are at the
top of the tree so giraffes
with longer necks survive
and pass these genes on to
the next generation whilst
giraffes with shorter necks
die out.
- Overtime, the mean giraffe
neck length gradually gets
longer (moves to the right)
with still room for variation
within the population.
- This continues over
generations till the “need” for
longer necks is no longer
present because they can
reach the leaves and
bidirectional evolution is no
longer relevant. - Balancing Selection:
- Moths come in different
pigmentation.
- Grey moths are able to blend
into birch trees well, but
white and dark grey moths
are easier to spot by
predators and some of them
die out whilst grey moths
reproduce.
- Overtime, the extremity of the
variation in pigmentation
lessens (i.e., white become
less white and dark grey less
dark, but they are still
disadvantaged relative to the
grey moths). - Disruptive Selection:
- Finch’s with three different
beak sizes. The larger beak is
good for breaking seeds, the
smaller beak is good for
eating bugs and the medium
size beak is not good at
either.
- The larger and smaller beaks
fill ecological niches and
these finches are able to
thrive and pass on their
genes whereas the finch with
a medium sized beak cannot
find enough food to survive
and dies out and the variation
between finch’s in a species
increases.
who is Ernst Mayr (1904-2005)
Published “the systematics and the origin of species” in which he defines a species as “Species are groups of actually or potentially interbreeding natural populations, which are reproductively isolated from other such groups” which is still debated today!
He tried to shift people’s
perceptions of what a species
is from visual variations in
species to genetic variation.
He publishes “cause and
effect in biology” where aims
to explain what causes animal
behaviour?
E.g., Why did the warbler start
his southward migration on the
night of the 25th of August?
He outlines (4) Tentative
Reasons:
- An Ecological Cause:
- Warblers eat insects and when
there is no longer sufficient
food in their environment they
migrate. - A Biological Cause:
- Warblers respond to this
environmental factor in a
genetically predetermined
way.
3. An Intrinsic Physiological Cause: - Photoperiodicity; an organisms response to changes in day length that’s internal.
4. An Extrinsic Physiological Cause: - A cold northerly wind passed through on the 25th August which triggered their migration. He then outlines two main types of causes: (A) Proximal Cause: - relevant motivators that occur within an organisms lifetime. (B) Ultimate Cause: - motivated by long-term things such as starvation; if everyone starves no one can reproduce.
who is Theodosius Dobzhansky (1900-1975)
He was influential because he writes a book which summarizes all the information they currently had on genetics. He got research started on fruit fly’s. “Nothing in biology makes sense except in the light of evolution” We start to see the shift towards people working on genetic explanations. Beyond the mechanisms of inheritance there are random mutations in individuals that are caused by external factors and lead to the miscoding of certain base pairs.
who is Julian Huxley (1887-1975)
He comes up with the term “modern synthesis” which summarises and synthesis the genetic view into Neo-Darwinism.
who is Trofim Lysenko
o During the cold war the soviet union outlawed geneticist research because it didn’t match their Marxism philosophy and Lamarckian theory. o He strongly peddled the Lamarkian theory within the soviet union and he believed that is you freeze peas and resow them they would be more resistant to frost-not true. o This lead to major starvation in the Soviet Union under Stalin’s regime.
who is Sir Ronald Aylmer Fisher (1890-1962)
o While working as a school teacher in London, he started analysing the rediscovered laws by Mendel and was the first to demonstrate mathematically that a large number of genes that work independently can produce continuous variation among phenotypic traits which was consistent with Mendel’s laws. o Caveat: • Don’t get too attached to fisher- whilst he came up with well-known theories, he was a eugenicist (selective reproduction to preserve desired traits and breed out undesirable traits). • He also found Mendel’s study to be too good to be true. His findings were statistically improbable and indicate biased research although it’s still a supported theory.
Darwins original theory of inheretence?
His natural selection theory claimed: ‘Any variation which is not inherited is unimportant’ …[t]he laws governing inheritance are quite unknown’. We know it’s not a good theory if you admit you do not know how a key element works. He produced the “The Provisional Hypothesis of Pangenesis” (Pan = whole, genesis = origin) which is the idea that there is a “Gemmulus”. Taking Herbert Spencer’s idea of physiological units within cells each cell in your body with small gemmules parts that shed off and allow for the blending of traits. E.g., Mother-Father mix and blend in the embryo to produce the traits of the offspring- we now know that this is not how inheritance works but back then they did not know about genetics.
Logical Flaws in This Theory of Inheretence: If you loose an arm you will no longer have these cell to shed their gemmulus and be passed down onto their offspring. Does this mean the offspring will be born with a deformity? Similar critique of Lamarckian Theory. If cells are mixed in the embryo as the theory suggests we would end up with indiscriminant equally distributed soup- varaition would not occur!
