ideas about biological diversity “except in the case of human behavior, we need not invoke nor can...

Ideas About Biological Diversity

• “Except in the case of human behavior, we need not invoke nor can we find any evidence for any design, goal, or purpose anywhere in the natural world.”– Douglas Futuyma

• Old ideas about biological diversity• Aristotle: scale of nature

• Ranking system

• Ranking represents levels of fixed

• diversity

• Higher – Lower forms

• One tenent of creationism

– fixity of species

– all created at the same time

– have persisted unchanged since

• their origins

• Idea subsequently altered by

• evolutionists such as Lamarck.

1 = Lamarkian Evolution; 2 = Darwinian Evolution

“Inheritance” of acquired characteristics1.

2.

Our Origins, 2nd EditionCopyright © 2011 W.W. Norton & Company

“Lamark’s classic example of inheritance of acquired characteristics.”Hypothesis can be tested.

Giraffe neck lengthAn adaptation

.

Does the long neck increase energy acquisition?

Two bull giraffesEngaged in competition

What Is So Different about Humans from Other Animals?

The Six Steps to Humanness: Humans differ from other animals in several important ways.1) Bipedalism (?)

Defined as walking on two feet2) Non-honing chewing

Reduction of canine size

3) Complex material culture and tool use Humans depend completely on culture for

day-to-day living and species survival. Other apes exhibit some forms of cultural

behavior. 4) Hunting

Group pursuit of animals for food

5 ) Speech The only animal that communicates by

talking 6) Dependence on domesticated foods

Development of ability to raise domesticated plants and animals