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passes down from parents to children and for an explanation as
to how exactly heredity happens.

HOW ARE TRAITS PASSED DOWN?
Another scientist researching at the same time as Darwin
was Gregor Mendel (1822–1884). Mendel was born into a
German-speaking family in what is now the Czech Republic,
and as an adult, he became a Catholic monk. As a monastic
teacher, Mendel spent almost a decade planting thousands of
pea plants in his monastery garden and studying their heredity
and evolution. He focused on seven plant traits: seed shape,
seed color, pod shape, pod color, stem length, the position of
the flower on the stem, and flower color. He cross-fertilized pea
plants with different traits to see which would appear in the next
generation. And he kept meticulous notes on his cross-pollination
of seedlings. His research showed a pattern and helped him
identify three laws of inheritance:

LAW OF SEGREGATION
Mendel’s law of segregation dictated that each parent plant
passes down to offspring a certain heritable element. In Mendel’s
experiment, these elements each came in two variants: white or
purple flower color, tall or short stem height, round or wrinkled
pea shape, yellow or green pea color, terminal or axial flower
position on the stem, inflated or constricted pod shape, and
yellow or green pod color. Scientists have come to understand
that Mendel’s heritable elements are genes, a unit of heritable
information, and the variants are alleles, alternate forms of a gene.

LAW OF INDEPENDENT ASSORTMENT
Mendel also discovered a law of independent assortment. This
law refers to how each trait is independent from the others.

Genomics
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