McGraw-Hill © 2008 The McGraw-Hill Companies, Inc. All Rights Reserved

McGraw-Hill © 2008 The McGraw-Hill Companies, Inc. All Rights Reserved

Theory A well-supported general idea that

explains a large set of factual patterns and predicts other patterns.

Science The method of inquiry that requires

the generation, testing, and acceptance or rejection of hypotheses.

McGraw-Hill © 2008 The McGraw-Hill Companies, Inc. All Rights Reserved

The Scientific Method Patterns, Associations, Connections Hypotheses Predictions Observations, Experiments, New

data

McGraw-Hill © 2008 The McGraw-Hill Companies, Inc. All Rights Reserved

The Evolution of Evolution How did our knowledge of the

history of living organisms move from the realm of belief systems to the realm of science?

How did the scientific evidence for evolution develop?

McGraw-Hill © 2008 The McGraw-Hill Companies, Inc. All Rights Reserved

How Do We Know That Evolution Has Occurred? The evidence for evolution has

primarily come from four sources: 1.    the fossil record of change in

earlier species 2. the chemical and anatomical

similarities of related life forms

McGraw-Hill © 2008 The McGraw-Hill Companies, Inc. All Rights Reserved

3. the geographic distribution of related species

4.  the recorded genetic changes in living organisms over many generations

McGraw-Hill © 2008 The McGraw-Hill Companies, Inc. All Rights Reserved

The Evolution of Evolution “On the Shoulders of Giants”:

Explaining the Changing Earth Through the work of Hooke, Steno,

Hutton, Smith, and Lyell-- and many others-- the study of the earth shifted from the supernatural to the natural.

McGraw-Hill © 2008 The McGraw-Hill Companies, Inc. All Rights Reserved

Evolution Change through time; here, with reference to

biological species.

Fossils Remains of life-forms of the past.

Strata Layers; here, the layers of rock and soil under

the earth’s surface.

Stratigraphy The study of the earth’s strata.

McGraw-Hill © 2008 The McGraw-Hill Companies, Inc. All Rights Reserved

Pre-Darwin theories on evolution The leading biological scientist of the

mid 18th century was the Swedish botanist Karl von Linné (Carolus Linnaeus) 1707-1778. He proposed a logical classification system for all living things which he proposed in his book Systema Naturae, taxonomy.

Jean-Baptiste Lamarck. 1744-1829. He believed that evolution was mostly due to the inheritance of acquired characteristics as creatures adapted to their environments. 

McGraw-Hill © 2008 The McGraw-Hill Companies, Inc. All Rights Reserved

George Cuvier, 1769-1832. He advocated the theory of catastrophism , as did most other leading scientists of his day.  Cuvier's explanation relied solely on scientific evidence rather than biblical interpretation.

Charles Lyell  , 1797-1875.   He  documented the fact that the earth must be very old and that it has been subject to the same sort of natural processes in the past that operate today in shaping the land. He provided conclusive evidence for the theory of uniformitarianism

McGraw-Hill © 2008 The McGraw-Hill Companies, Inc. All Rights Reserved

Darwin and Natural Selection Charles Darwin, 1809-1882

McGraw-Hill © 2008 The McGraw-Hill Companies, Inc. All Rights Reserved

Darwin identified 13 species of finches in the Galápagos Islands

McGraw-Hill © 2008 The McGraw-Hill Companies, Inc. All Rights Reserved

Darwin identified 13 species of finches in the Galápagos Islands

He concluded that when the original South American finches reached the islands, they dispersed to different environments where they had to adapt to different conditions

Today we use the term adaptive radiation to refer to this sort of branching evolution in which different populations of a species become reproductively isolated from each other by adapting to different ecological niches and eventually become separate species.

McGraw-Hill © 2008 The McGraw-Hill Companies, Inc. All Rights Reserved

Darwin came to understand that any population consists of individuals that are all slightly different from one another.  Those individuals having a variation that gives them an advantage in staying alive long enough to successfully reproduce are the ones that pass on their traits more frequently to the next generation.  

McGraw-Hill © 2008 The McGraw-Hill Companies, Inc. All Rights Reserved

Darwin did not believe that the environment was producing the variation within the finch populations.  He correctly thought that the variation already existed and that nature just selected for the most suitable beak shape and against less useful ones.

McGraw-Hill © 2008 The McGraw-Hill Companies, Inc. All Rights Reserved

definitions

Catastrophists Those who believe the history of the earth is

explained by a series of global catastrophes, either natural or divine in origin.

Comparative Anatomy Comparing the anatomical features of various

species. Used to reconstruct a fossil species from fragmentary remains.

Uniformitarianism The idea that present-day geological processes can

also explain the history of the earth.

McGraw-Hill © 2008 The McGraw-Hill Companies, Inc. All Rights Reserved

The Evolution of Evolution “Common Sense At Its Best”:

Explaining Biological Change Charles Darwin was born into a world

that accepted the fact of biological change but was still in search of a mechanism for that change.

Lamarck’s model of inheritance of acquired characteristics applied to the evolution of long necks and tall bodies in giraffes.

McGraw-Hill © 2008 The McGraw-Hill Companies, Inc. All Rights Reserved

definitions

Adaptation The state in which an organism is

adjusted to and can survive in its environment through its physical traits and behaviors. Also, the process by which an organism develops this state through natural processes.

McGraw-Hill © 2008 The McGraw-Hill Companies, Inc. All Rights Reserved

definitions

Progressive In evolution, the now-discounted idea

that all change is toward increasing complexity.

Inheritance of acquired characteristics The incorrect idea that adaptive traits

acquired during an organism’s lifetime can be passed on to its offspring.

McGraw-Hill © 2008 The McGraw-Hill Companies, Inc. All Rights Reserved

definitions

Fitness The relative adaptiveness of an

individual organism, measured ultimately by reproductive success.

Natural Selection Evolutionary change based on the

differential reproductive success of individuals within a species.

McGraw-Hill © 2008 The McGraw-Hill Companies, Inc. All Rights Reserved

The Evolution of Evolution Summary

As the scientific method was applied to the study of the earth, scientists gradually learned to give up their presuppositions.