NATURAL SELECTIONTHEORYHARUN HUSSAIN

What Is A Scientific Theory? A scientific theory is a well

proven hypothesis of some part of the natural world

A hypothesis is an idea that can become a theory

It is developed through the scientific method by testing repeatedly

It is then confirmed through observations and experimentations

How is it developed? Understand the basics of science Make observations Gather all your observations and

create a hypothesis Make predictions based on your

hypothesis Do an experiment to test your

predictions Blind and double blind trials Evidence to support your

hypothesis and get it peer reviewed

What Is Natural Selection? This is a theory by Charles Darwin and

Alfred Russel This is the process where organisms

better adapted to their environment tend to survive and produce more offspring

Natural Selection is basically an explanation for the mechanism of Evolution

Who Came Up With This Theory? This is a theory by Charles Darwin and Alfred Russell Both scientists were making observations of the

geographical distributions of species They found that different species were found in different

environments The theory tells us that there are variations in

organisms of the same species for example: Some are tall Some are short Some are fat Some are thin etc. http://darwin200.christs.cam.ac.uk/pa

ges/index.php?page_id=d3

Charles Darwin Darwin was a British scientist He was born on the 12th February 1809 in Shrewsbury In 1831 he joined a 5 year scientific expedition on the

survey ship HMS Beagle On his return to England he tried to solve the riddles of

these observations & the puzzles of how species evolved From this he came up with the evolution theory by the

process of Natural Selection Darwin died on the 19th April 1882http://www.bbc.co.uk/history/historic_figures/darwin_charles.shtml

Alfred Russell Wallace Alfred Russell Wallace was a British humanist, naturalist,

social critic and geographer He was born in Monmouthshire, Wales on the 8th January

1823 In the second half of the 19th Century he became a public

figure in England He came up with a formulation of the theory of evolution

by Natural Selection and joined Darwin to come up with this theory

He died on the 7th November 1913http://www.britannica.com/EBchecked/topic/634738/Alfred-Russel-Wallace

Main Points Of The Theory… The following briefly states the main points on

the theory of Natural Selection: Variations amongst individuals of the same

species Resources are limited Organisms reproduce Organisms compete against one another, i.e.

for food, shelter etc The fittest survive, they reproduce and pass on

useful traits to the next generation

Development of the theory… Darwin saw that organisms produce more

offspring than is needed to replace themselves, which would mean population sizes would increase

Darwin confirmed his observations with others, that population numbers tend to stay the same level

He found that resources such as food, water, places to sleep and mate are limited

He was reading work on Thomas Malthus who stated ‘Human population was increasing at a rapid pace and would soon run out of resources’

He put these facts together to draw a conclusion that individuals compete with each other for resources

http://darwin200.christs.cam.ac.uk/pages/index.php?page_id=d3

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He then made 2 other observations on individuals He found out that individuals are unique and that

they vary in almost every aspect

Himself and Russell then investigated variability by breeding pigeons because they realized that if an animal has some trait that helps it to survive the elements or to breed, it may leave more offspring behind

After some time himself and Russell argued that natural selection might produce new types of body parts from eyes to wings

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

He then saw that individuals will have variations which will give them a survival boost. This will give them more time to…

He then finally concluded that over time the population will change and that is his theory of evolution through Natural Selection

http://darwin200.christs.cam.ac.uk/pages/index.php?page_id=d3

Reproduce Leave a greater number

of offspring

Evidence Darwin wrote ‘an unverified

hypothesis is of little or no value’

To verify this he collected a load of facts from different fields

He assembled reports from other naturalists as well as from his observations

It was hard for him to convince the people at the time, but he demonstrated a test on breeding domestic animals and plants for Natural Selection

Joseph Dalton Hooker arranged for both Darwin's and Wallace's theories to be presented to a meeting of the Linnaean society in 1858

Since 1859 the scientist community has been testing both of the scientists theories. Now it includes evidence from DNA records, fossil records and from case study sections.http://darwin200.christs.cam.ac.uk/pages/index.php?page_id=d3

What Are The Limitations Of Science…

Questions Science Has Answered

Why does hair turn grey? Scientists say stress turns your hair grey

as well as genetic factors.

A pigment called melanin makes the hair go a certain colour, but if that melanin is lost the hair starts to go grey, but hairs that lose all there pigment turn white

"There is evidence that local expression of stress hormones mediate the signals instructing melanocytes to deliver melanin to keratinocytes," notes Jennifer Lin, a dermatologist who conducts molecular biology research at the Dana-Farber / Harvard Cancer Centre in Boston. "Conceivably, if that signal is disrupted, melanin will not deliver pigment to your hair.“

http://www.scientificamerican.com/article/fact-or-fiction-stress-causes-gray-hair/

What came first the chicken or the egg?

The chicken actually came first and many scientists have answered and proven this fact.

‘It had long been suspected that the egg came first but now we have the scientific proof that shows that in fact the chicken came first,’ said Dr Colin Freeman, from Sheffield University, who worked with counterparts at Warwick University.

http://metro.co.uk/2010/07/13/the-chicken-came-first-not-the-egg-scientists-prove-447738/

Questions Science Are Currently Addressing Are we alone in the

universe? Nasa scientists say we are not alone

in the universe "I think in the next 20 years we will

find out we are not alone in the universe," NASA astronomer Kevin Hand said in footage filmed at the discussion and posted on YouTube.

http://www.huffingtonpost.com/2014/07/15/we-are-not-alone-in-universe-nasa-habitable-planets_n_5588455.html

• Is there a cure for cancer?

At the moments there isn't a cure for cancer. Its not a single disease, but a group of many diseases, cancer has been around since the dinosaurs and being caused by haywire genes, the risk is hardwired into all of us.

Scientists say ‘trough genetics we're learning more and more about what causes it, how it spreads and we are getting better at treating and preventing it’

http://www.theguardian.com/science/2013/sep/01/20-big-questions-in-science

Questions That Science Can Never Answer Is there a God? This is a question that science can never

answer, because most scientists believe that the world started with a big bang, on the other hand other scientists believe there is a God and that God created the whole universe.

Scientists do not have evidence that God does or does not exist.

The big bang theory states that the universe started of from a tiny particle which the scientist now call ‘The God Particle’

Science nor religion can ever answer this questions…some scientists ask… Before there was something, there was nothing.

And out of nothing, how did we get something? What existed before the big bang, before creation, and before God?

http://www.wfs.org/blogs/thomas-frey/ten-questions-neither-science-nor-religion-can-answer

Why does time exist? Everyone thinks of time differently

for example; some think it’s a setting sun, some think it’s a theory of physics and to others a philosophy to be debated

So everyone has different conceptions on why time exists, which makes it hard to answer ‘why time exists’

Albert Einstein stated, “the only reason for time is so that everything doesn’t happen at once.”

He also said “no further explanation will be forthcoming.”

http://www.wfs.org/blogs/thomas-frey/ten-questions-neither-science-nor-religion-can-answer

Resistance In New Scientific Theories

There is resistance to new scientific theories because there is not enough evidence to support these new theories

More tests and research needs to be carried out before these theories can be proved

The community of scientists rely upon each other to test each others theories, methods and even repeatedly tested experiments and their outcomes.

Sometimes new theories have to be tested, however scientists don’t have all the technology to carry out tests for a new theory, but in time when they have the technology they will be able to test these theories.

http://www.enotes.com/homework-help/why-there-sometimes-resistance-new-scientific-392880

Examples Of Resistance To New Theories Darwin’s theory was materialist at a time when

materialism wasn’t just unpopular in respectable circles, it was considered destabilising and politically dangerous.

Whilst he was working on his theory from 1838 to 1848, England was going through political protests and strikes.

Darwin wasn’t strong in the political region he wasn’t into politics

Darwin was writing a book called ‘On the Origin of Species by Means of Natural Selection’ this was published in 1859

After it was published it was the best seller and on top of that many scientists accepted his theory, but not all

His theory was judged by the scientific institution and by religious leaders.

The critics continuously raised two related arguments:

That natural selection excluded any role for God Also that although Darwin had cautiously avoided

the subject, human beings must also be goods of natural selection. Both ideas were wrong so that’s why Darwin's theory wasn’t accepted at an early stage, there was a lot of resistance and later on scientists realised he was right so they accepted his theory

http://socialistresistance.org/303/charles-darwin-reluctant-revolutionary