Evolution and Zoology

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Reynold McCormick
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1 EVOLUTION

Evolution and Zoology Evolution is the foundation of biology and, thus, zoology. Evolution by Natural Selection has shaped every organism that has ever existed on this planet.

2 Evolution and Zoology Evolution is the foundation of biology and, thus, zoology. Evolution by Natural Selection has shaped every organism that has ever existed on this planet. Animals look and act the way they do because of evolution. If we are going to understand the animal kingdom, we must first understand evolution. There s a reason the peacock has evolved those extravagant feathers

3 Evolution fact or theory? Scientific Theory: A scientific theory is a well-substantiated explanation of some aspect of the natural world, based on a body of facts that have been repeatedly confirmed through observation and experiment. Such fact-supported theories are not "guesses" but reliable accounts of the real world. Do you believe in gravity? Then you believe in evolution. More accurately, you don t believe in either. You accept them to be true because the preponderance of evidence convinces you.

4 The Blue Moon Butterfly Fastest example of evolution on record. Significant change in population in less than a year; only 10 generations. Wolbachia bacteria selectively killed male embryos By 2001 males comprised only 1% of the population In 2005 researchers found a single male In 2006 researchers discovered males comprised 40% of the population Dominant suppressor gene found that provided bacterial resistance

5 The History of Evolution Evolution = species change over time First posed by Greek philosopher, Anaximander, over 2,500 years ago Relied on reason to argue that men arose from fishes Mermaids are Real

6 Then why is it still so controversial?

The Definition of Evolution Google: the process by which different kinds of living organisms are thought to have developed and diversified from earlier forms during the history of the earth.

7 The Definition of Evolution Google: the process by which different kinds of living organisms are thought to have developed and diversified from earlier forms during the history of the earth. Dictionary.com: any process of formation or growth; development: FreeDictionary.com: A gradual process in which something changes into a different and usually more complex or better form. Merriam-Webster: a theory that the differences between modern plants and animals are because of changes that happened by a natural process over a very long time (Simple) OR a theory that the various types of animals and plants have their origin in other preexisting types and that the distinguishable differences are due to modifications in successive generations; also : the process described by this theory YourDictionary.com: the development of a species, organism, or organ from its original or primitive state to its present or specialized state; phylogeny or ontogeny The OED: The process by which different kinds of living organisms are thought to have developed and diversified from earlier forms during the history of the earth. Cambridge Dictionary: Evolution is the process by which the physical characteristics of types of creatures change over time, new types of creatures develop, and others disappear.

8 A proper biological definition referencing THE EVOLUTION OF LIVING ORGANISMS The change in genetic composition of a population over successive generations A.K.A. The change in allele frequency of a population over successive generations

9 Micro vs. Macro microevolution: change in allele frequency over successive generations macroevolution: evolutionary change at the species level or higher; speciation

lab, domestication FACT is correct term 2.

the context to settle it Ultimate framework of biology; especially ecology 3.

10 Three Levels of Consideration 1. The fact of evolution Well established Plethora of evidence fossil record, lab, domestication FACT is correct term 2. The mechanism of evolution Natural selection Darwin s contribution Provided the context to settle it Ultimate framework of biology; especially ecology 3. The course of evolution What, precisely, led to what? Much more debatable Postulations and theories still hotly contested - particularly in regards to humans

In the process of getting it right, science often first gets it wrong Species are fixed (never change) A bison has always been a bison and will always be a bison Context: Before rigorous science was

11 In the process of getting it right, science often first gets it wrong Species are fixed (never change) A bison has always been a bison and will always be a bison Context: Before rigorous science was the norm Before widespread printing of books (1800s) Before mass education (1800s) When religion still dominated every aspect of society (God does not make mistakes) Cave painting, France, c. 30,000 ya

John Ray: The Wisdom of God Manifested in the Works of Creation (1691) Lice breed in beds and

12 Explain the Weird If God doesn t make mistakes, how do you explain really annoying and weird things like lice? Rev. John Ray: The Wisdom of God Manifested in the Works of Creation (1691) Lice breed in beds and clothes so this is clearly, an effect of divine providence, designed to deter men and women from sluttishness and sordidness, and to provoke them to cleanliness and neatness.

believed that species do not change Many scientists tried to avoid strictly

13 Even scientists making strides still held onto misconceptions Carolus Linnaeus ( ) Still use his system of classification today Firmly believed that species do not change Many scientists tried to avoid strictly biblical explanations Hard to completely overcome something so firmly rooted in your culture

14 Puzzle Activity What is the Teacher s Rule?

Why we hold so tightly to our misconceptions "A MAN WITH A CONVICTION is a hard man to change. Tell him you disagree and he turns away. Show him facts or figures and he questions your sources.

15 Why we hold so tightly to our misconceptions "A MAN WITH A CONVICTION is a hard man to change. Tell him you disagree and he turns away. Show him facts or figures and he questions your sources. Appeal to logic and he fails to see your point. --Leon Festinger, Stanford Univeristy The Research Shows: Emotions surface in miliseconds resulting in fast gut reactions Evolution has favored this so it is very ingrained Reasoning and logic come much slower and with much less force The negative emotional response dictates how the brain processes the succeeding information and determines what memories are stored The natural, subconscious tendency, is to bolster what we already believe and ignore new information

Conservatism Bias We prefer to believe what we already believe

16 Cognitive Biases 1. Anchoring Bias We are over-reliant on the first piece of information we hear or learn 2. Choice Supportive Bias We like our own choices, even when they are flawed 3. Availability Heuristic We place too much importance on a single example (anecdotal fallacy) 4. Confirmation Bias We prefer information that proves us right 5. Conservatism Bias We prefer to believe what we already believe 6. Selective Perception Our expectations influence how we perceive the world 7. Zero-risk Bias Risk is scary, certainty is safe; we love certainty 8. Blind-spot Bias We are terrible at recognizing our own cognitive biases

17 Homework Find one example of a cognitive bias in yourself or someone you interact with today. Compose a paragraph in your journal explaining it.

18 A few take the risk to propose something radical and still get it a little wrong. Lamarckian Evolution (1809): A need is present, a trait develops to meet that need, that acquired trait is passed on to successive generations.

19 Or was he.? Epigenetics Gene expression patterns can be inherited differently in otherwise genetically identical individuals. This can be influenced by environmental factors.

Charles Darwin Born February 1809 in England to a successful physician Tried medicine at Oxford, but didn t care for it Father tried to pressure him into a career in the Church Had an interest in

20 Charles Darwin Born February 1809 in England to a successful physician Tried medicine at Oxford, but didn t care for it Father tried to pressure him into a career in the Church Had an interest in natural history that was encouraged at Cambridge In 1831, at age 22, defied father to join crew of H.M.S. Beagle Spent 5 years traveling the world and acting as the ship s Naturalist Vast array of life intellectually transformed him The Galapagos Islands off the coast of Ecuador especially important Struggled to stick to his preconceived ideas that God had created everything he had seen and all the specimens he had collected in their exact and present form

Epiphany helped by an economist Had no mechanism to explain the diversification Studied and inventoried collection for 2 years Read an essay on population by Thomas Malthus Economist On the Principle

21 Epiphany helped by an economist Had no mechanism to explain the diversification Studied and inventoried collection for 2 years Read an essay on population by Thomas Malthus Economist On the Principle of Population (1798) Population growth would always outstrip resources Results in perpetual hunger, disease, and struggle Applied the same idea to populations of animals Realized that a similar situation exists in nature; populations produce more offspring than can be supported Some individuals would be naturally suited to combat this struggle better than others Those individuals would disproportionately survive and pass on their traits to the next generation

22 But this will change. everything Darwin fully understood the implications of his discovery He was a careful man and wanted more time to gather more evidence He did not publish his ideas and only tactfully discussed them in limited ways He tucked a draft into a desk drawer with money and instructions to publish if he died He did not make his ideas public.. For 20 years

Competition A young naturalist, Alfred Russell Wallace, finally gave Darwin the reason to publish Russell had been traveling the world, collecting

by Malthus on population, limited resources, and famine It occurred to me to ask the question: Why do some die and some live?

23 Competition A young naturalist, Alfred Russell Wallace, finally gave Darwin the reason to publish Russell had been traveling the world, collecting specimens to sell to museums While in the east, near Borneo, he fell very will with fever His feverish mind recalled an essay he had read earlier. by Malthus on population, limited resources, and famine It occurred to me to ask the question: Why do some die and some live?...the answer was clearly ever present variability would furnish the material from which, by the mere weeding out of those less adapted to the actual conditions, the fittest alone would continue the race.

On the Origin of Species Knowing Darwin was interested in similar ideas, Wallace immediately wrote a letter about his new idea and posted it to Darwin

subject which was read to the Linnean Society in July of 1858 Darwin proceeded to publish a 500 page first edition of his cornerstone On the Origin of

24 On the Origin of Species Knowing Darwin was interested in similar ideas, Wallace immediately wrote a letter about his new idea and posted it to Darwin The post took four months to reach Darwin, but hit him like a bolt out of the blue To the credit of both, they agreed to publish a joint paper on the subject which was read to the Linnean Society in July of 1858 Darwin proceeded to publish a 500 page first edition of his cornerstone On the Origin of Species was published on November 24, 1859 The dramatic effect was immediate and sustained Darwin continued to publish expanded work, including The Decent of Man

Obstacles TIME YOUNG EARTH: In the 1600s, an Archbishop used the Bible to determine that (Christian) creation began on Saturday, October 22, 4004 B.C. Dr.

6000 years is not long enough for evolution to have taken place Even science still had it wrong: Kelvin calculated the earth to be 24 million years old based on a constant cooling rate BLENDING

25 Obstacles TIME YOUNG EARTH: In the 1600s, an Archbishop used the Bible to determine that (Christian) creation began on Saturday, October 22, 4004 B.C. Dr. Lightfoot at Cambridge University then calculated that humans would have been created 5 days later on Thursday, October 27, at 9:00 a.m. These precise calculations by respected scholars stuck years is not long enough for evolution to have taken place Even science still had it wrong: Kelvin calculated the earth to be 24 million years old based on a constant cooling rate BLENDING DILUTION OF TRAITS Popular view was traits were a blended mix of parental traits If so, how did variation necessary for species change arise? The process dilutes superior traits out of existence Only middle remains, nothing for natural selection to work on

Controversy RELIGION Religious leaders, powerful and influential in the Victorian era, immediately denounced Darwin and dismissed his ideas outright Viewed as a direct, existential threat to many

26 Controversy RELIGION Religious leaders, powerful and influential in the Victorian era, immediately denounced Darwin and dismissed his ideas outright Viewed as a direct, existential threat to many core tenants of the church and, as such, was heretical Darwin pointed out evolution and theism were not mutually exclusive Darwin was a self described agnostic, but was also very respectful of religious views, refused to classed as an atheist, was very mindful about offending devout people, and agonized over the controversy his ideas caused Writing to a friend: I had no intention to write atheistically. But, he went on, I cannot see as plainly as others do evidence of design and beneficence on all sides of us. There seems to be too much misery in the world. NOTED SCIENTISTS, POLITICIANS, FRIENDS Many respected scientists could not accept Darwin s ideas because there was no special place for man A powerful politician, and future prime minister, refused to be associated with apes and sided with angels The captain, and friend to Darwin, of the HMS Beagle sided against Darwin s ideas

27 When was evolution accepted by science? Answer depends. As with all scientific revolutions, it takes time because it takes lots of review and debate and work until enough evidence mounts that consensus is finally reached. Advances were made in many fields genetics, population genetics, paleontology, biogeography, taxonomy, and animal behavior over the course of the next 80 years. In the 1930s and 1940s, the modern synthesis of evolution fully crystallized and became widely accepted. Since, evidence has continued to mount in support of evolution by natural selection.

Introduction to Evolution. DANILO V. ROGAYAN JR. Faculty, Department of Natural Sciences

Introduction to Evolution. DANILO V. ROGAYAN JR. Faculty, Department of Natural Sciences Introduction to Evolution DANILO V. ROGAYAN JR. Faculty, Department of Natural Sciences Only a theory? Basic premises for this discussion Evolution is not a belief system. It is a scientific concept. It