1. Scientific and Medical Achievements
Main Idea
Advances in science, medicine, and the social sciences led to new theories about the natural world and human mind, an improved quality of life, and longer life spans.
Reading Focus
What were some of the new ideas in the sciences?
What medical breakthroughs affected the quality of life?
What new ideas developed within the social sciences?

2. Charles Darwin studied variations in plants, animals in 1800s
New Ideas in Science
Charles Darwin studied variations in plants, animals in 1800s
Published theories in On the Origin of Species
Developed concept of natural selection
Creatures well adapted to environment have better chance of surviving, producing offspring
Offspring will inherit features that help them survive

3. Darwin’s Theory of Evolution
New Ideas in Science
Darwin’s Theory of Evolution
Over time the species will evolve to improve survival chances
Controversial theory
Indicated humans were descended from other animals
Many opposed Darwin because theory differed from Biblical story of creation

4. More Elements Discovered
New Ideas in Science
Modern Atomic Theory
John Dalton, 1803
Atoms of different elements are themselves of difference size and mass
Periodic Table
Dimitri Mendeleyev, 1871
Arranged known chemical elements into Periodic Table
Revealed previously unknown patterns
More Elements Discovered
Marie and Pierre Curie, 1898
Discovered polonium, radium
Concluded certain elements release energy when break down, called radioactivity

5. Ernest Rutherford developed theories based on Curies’ work in 1911
New Ideas in Science
Ernest Rutherford developed theories based on Curies’ work in 1911
Called center of atom a nucleus
Nucleus made up of positively charged particles, protons
Disproved belief that atom was solid piece of matter

6. New Ideas in Science Einstein’s Genius
Albert Einstein revolutionized physics
Used math to show light can act like particles of energy
No particle of matter can move faster than speed of light
Motion can be measured only from viewpoint of observer
Einstein’s Genius

7. E = mc2
Small amount of mass can be converted into huge amount of energy
Space is curved, must include time in study of space
Work led to study of nuclear power

8. Medical Breakthroughs
Preventing Disease
Breakthroughs in late 1800s as result of scientific advances earlier in century
Fundamental concepts of disease, medical care, sanitation revealed
Mysteries of what caused diseases began to be solved
Microbes and Disease
Louis Pasteur showed link between the two, 1870
Disproved spontaneous generation concept of bacteria from nonliving matter
Showed bacteria always present though unseen, can reproduce
Fermentation
Bacteria in the air causes grape juice to turn to wine, milk to sour
Heating liquids, foods can kill bacteria, prevent fermentation
Process became known as pasteurization, makes foods germ-free

9. Medical Breakthroughs
Anthrax
Deadly disease a constant threat to people, livestock
Pasteur sought to prevent anthrax
Injected animals with vaccine containing weakened anthrax germs
Antibodies
Vaccine worked because body builds antibodies
Antibodies fight weakened germs when they enter body
Rabies
Pasteur’s next goal
Developed vaccine, 1885
Saved life of young boy bitten by rabid dog

10. Medical Breakthroughs
Improving Medical Care
Treatment of pain
American surgeon Crawford W. Long
Discovered solution to pain suffered by surgery patients
Patients breathed in ether, an anesthetic to reduce pain and render patient unconscious
Performed first painless operation, 1842

11. Ether Surgery

12. Medical Breakthroughs
Treatment of Infections
Many surgical patients died from infections
English surgeon Joseph Lister, 1860s
Began cleaning wounds and equipment with antiseptic containing carbolic acid
Reduced post-surgery deaths in one hospital ward from 45 to 15 percent

13. Medical Breakthroughs
Public health improved with building of more modern hospitals
More medical professionals trained
Nursing schools trained large numbers of women, some trained as doctors
By 1900, 5 percent of American doctors were women
Hospitals
Caused dramatic decline in infant mortality
Statistics from Sweden provide example
1800, 240 infant deaths in first year per 1,000 live births
Nearly 100 years later, only 91 infant deaths in first year per 1,000 live births
Improved Care

14. New Ideas in Social Sciences
In the late 1800s scientists expanded their focus to include the study of the mind and human societies. These new fields became known as the social sciences and include psychology, archaeology, anthropology, and sociology.
Study of mind, human behavior became separate field in 1890s
Observation, experiments helped psychologists explore subject
Ivan Pavlov studied dogs to show animals could be taught certain reflex actions
Psychology

15. New Ideas in Social Sciences
Studies of human behavior
Sigmund Freud
Said that unconscious part of mind contains thoughts of which one is unaware
Used hypnotism to explore patient’s unconscious mind
Felt that repressed thoughts revealed in dreams could cause mental illness
Developed psychoanalysis as therapy

16. New Ideas in Social Sciences
Just as Freud studied individuals, other scientists studied people as members of groups, communities of people with a common culture.
Study of the past based on artifacts
Not new field of study
Early expeditions little more than treasure hunts
Began more scientific approach, mid-1800s
Carefully recorded all stages of work and preserved finds for education
Archeology
Study of humanity and human ancestors
Physical anthropologists interested in how Homo sapiens developed
Cultural anthropology deals with structures of societies, became separate field 1920s
Cultural anthropologists study cultures other than their own
Anthropology

17. New Ideas in Social Sciences
Sociology
Closely related to anthropology
Emerged as social science late 1800s
Sociologists study people in groups
Usually groups are in own societies
Examine societies’ institutions and sub-groups
Sub-groups organized around racial or ethnic identity, gender, or age