1. EARLY IDEAS GENETICS OF INHERITANCE

2. Hippocrates (460 – 377 B.P.)
every part of the body was involved in the production of “seeds”
The seeds would fuse together to make a new person

3. ARISTOTLE (384- 322 B.C.E) Theory of Pangenesis
Egg and sperm consist of particles  pangenes from all parts of body
upon fertilization the pangenes developed into the parts of the body from which they were formed.

4. WILLIAM HARVEY (1578 – 1657)
New individual arose through the process of EPIGENESIS
 embryo grew in stages and was affected by factors both inside and outside of the mother

5. ANTON VAN LEEUWENHOEK (1632 – 1723)
Used a microscope to examine gametes
found “animalcules” in semen and decided they were preformed embryo’s
Female contribution was only the influence of the uterus during embryo development

6. BLENDING THEORY Characteristics of parents blended in the offspring
Blending was irreversible, thus original characteristics would not appear in future generations

7. FRANCIS GALTON (1870’s)
Disproved the theory of pangenesis (still influenced biology 100 years ago)
Genes formed in every organ of both male and female body and moved to genitals

8. CHARLES DARWIN (1809 – 1882)
Offspring have variations of their parents characteristics
Couldn’t explain why – suggested current science had not yet discovered the puzzle pieces yet

9. Mendel’s law of heredity
GREGOR MENDEL (1822 – 1884)
Developed the fundamental principles of modern genetics
Experimented on pea plants and proposed
Mendel’s law of heredity