Evidence for Evolution:
Selective Breeding
Selective breeding of domesticated animals and crop plants provides
compelling evidence for evolution. This process, known as artificial
selection, demonstrates how human intervention can rapidly change
species over time.
by Kris Sherdley
Defining Artificial Selection
Human-Driven Process
Humans choose which organisms will reproduce based on desired
traits.
Intentional Selection
Specific characteristics are favored to enhance certain qualities in
offspring.
Controlled Breeding
Mating pairs are carefully selected to produce offspring with desired
traits.
Generational Changes
Traits become more pronounced or common over successive
generations.
Reasons for Selective Breeding
1
Increased Productivity
Breeding for higher yields in crops and livestock to meet growing
food demands.
2
Disease Resistance
Developing plants and animals that can withstand common
pathogens and pests.
3
Aesthetic Appeal
Creating ornamental plants and animals with unique or attractive
features.
4
Adaptation to Environment
Breeding species that can thrive in specific climates or
conditions.
Rapid Evolutionary Change
1
Initial Population
2
Trait Selection
3
Controlled Mating
4
Generational Progress
5
Rapid Change
A group of organisms with varied traits is selected for breeding.
Individuals with desired characteristics are chosen to reproduce.
Selected individuals are bred, passing on favorable traits to offspring.
Desired traits become more prominent in subsequent generations.
Within few generations, population shows significant changes from original group.
Artificial Selection in Crop Plants
Wild Cabbage
Selective Breeding
Diverse Vegetables
Ancient wild mustard plant with
Humans selected for different
Resulted in broccoli, cauliflower,
small, bitter leaves.
traits over centuries.
kale, and Brussels sprouts.
Artificial Selection in Domestic
Animals
Wild Wolves
1
Ancient ancestors of modern dogs, with diverse traits.
Early Domestication
2
Humans selected friendlier wolves for companionship and
hunting.
Breed Development
3
Specific traits selected for various purposes: herding,
hunting, companionship.
Modern Dog Breeds
4
Resulted in over 300 distinct breeds with diverse
characteristics.