Biology and the Scientific Method

The Scientific Method

• Francis Bacon codified the Scientific Method, influenced by Ibn al-Haytham’s centuries-old methods of inquiry.
• Bacon is credited with founding empiricism, advocating for testing knowledge through inductive reasoning and observation.
• Tragically, Bacon died from bronchitis after experimenting with the effects of cold on meat.

Defining Species

• John Ray, an English naturalist, provided the first biological definition of a species in his "Historia Plantarum."
• Ray defined species as morphologically similar organisms sharing a common ancestor.
• The modern definition of a species encompasses organisms capable of producing fertile offspring.

The Earth's Geological History

• James Hutton, a Scottish geologist, observed Siccar Point in Scotland, recognizing the vast time spans represented in geological formations.
• Hutton concluded that sedimentary rocks form in oceans, uplift into mountains through volcanic activity, and erode back into the ocean, creating a cyclical process.
• Hutton’s "Theory of the Earth" proposed vast time scales required for these geological processes, challenging biblical creation narratives.

Charles Lyell and Uniformitarianism

• Charles Lyell, a Scottish geologist and friend of Darwin, expanded on Hutton's work, arguing that deeper rock layers are older.
• Lyell’s "Principles of Geology" established the field as a science, emphasizing uniformitarianism—the idea that current geological processes explain past events.

Lamarck’s Theory of Inheritance of Acquired Characteristics

• Jean-Baptiste Lamarck, a French scientist, proposed a mechanism for species change over time, recognizing the environment's influence.
• Lamarck’s theory, known as the "Theory of Inheritance of Acquired Characteristics," emphasized that acquired traits are passed down to offspring.

Urban Evolution

• Urban environments dramatically alter landscapes, creating new habitats and influencing biodiversity.
• Crested anoles in Puerto Rico demonstrate rapid evolution in behavior and genetics as a result of urban pressures.
• City-dwelling anoles have developed longer limbs for faster movement, longer toe pads for clinging to smooth surfaces, and genetic distinctions from forest-dwelling populations.

Evolution in Action

• Evolution can occur in fits and starts and lacks a predetermined direction, influenced by environmental changes, climate, food availability, predation, and other factors.
• The eel-like creature Qikiqtania wakei demonstrates evolution's potential for reversals—evolving from fish to land-walker and back to water dweller.

Misconceptions about Evolution

• Natural selection does not create entirely new structures; it acts upon existing variation, favoring traits that improve survival and reproduction.
• The idea that humans might rapidly evolve gills and webbed feet in response to rising sea levels is a misconception.