9781422276143

The mystery of inheritance has intrigued people since ancient times. Many early philosophers and scientists tried to find out how traits passed from one generation to another. Archaeologists have found Babylonian clay tablets dating back to 6,000 years ago that recorded the pedigrees of horses and their desirable traits. Early Theories One of the first theories of inheritance was proposed by Pythagoras, the great Greek philosopher and mathematician in the 6th century BC. He proposed that the bodies of animals released some kind of vapor, and that new individuals were formed from the combination of these vapors. Fast-forwarding to the 19th century, Charles Darwin proposed the theory of pangenesis. Darwin stated that the organs produced tiny heredity particles called gemmules. These particles migrated to the gametes and passed on the characteristics to the offspring. However, like most other ancient theories, this theory did not hold up. Why the Theories Failed Most of these theories suggested that the characteristics of the parents get blended during transmission to the offspring, and therefore they

WORDS TO UNDERSTAND

chest cavity: the cavity or hollow space in the chest enclosed by ribs between diaphragm and neck. mucus: a thick fluid produced by some tissues that contains dead microorganisms pathogens: infectious microbes capable of causing disease.

9

Made with FlippingBook - professional solution for displaying marketing and sales documents online