Science 9 Unit A: Biological Diversity Science InAction Section 1.3: Pages Section 2.1: Pages 26-29

Lesson #3 Learner Outcomes I can identify the role of variation in species survival under changing environmental conditions I can describe examples of variation of characteristics within a species, and identify examples of both discrete and continuous variation I can distinguish those characteristics that are heritable from those that are not heritable, and identify characteristics for which heredity and environment may both play a role

What is Variation? Variability within a species population. Variability within a species population. Eg. Red/Blond Hair vs. Brown Hair Eg. Blue eyes vs. Green eyes Examples of variability in include: Red fox (color of coat) Antibiotic resistance (bacteria) Banded snail (color and design of shell)

Variation of Human Physical Characteristics Skin, eye, complexion colouring Skin, eye, complexion colouring Hair colour, baldness Hair colour, baldness Supernumerary body part (extra parts), or missing body parts Supernumerary body part (extra parts), or missing body parts Cleft Lip and Palate Cleft Lip and Palate

Variation of Human Physical Characteristics Height – average range Height – average range 1. Dwarfism 2. Gigantism Blood type Blood type - Groups A, B, AB, and O Somatotype Somatotype Dominance of handedness Dominance of handedness Dexterity and motor skills Dexterity and motor skills

Who is This Man?

What is Natural Selection? Happens when factors in the environment determines, or “selects” which individuals, within a species, will be able to survive. Happens when factors in the environment determines, or “selects” which individuals, within a species, will be able to survive. Offspring will usually have similar adaptations for survival. Whales Offspring will usually have similar adaptations for survival. WhalesWhales Charles Darwin – Theory of Evolution – “On the Origin of Species” book Charles Darwin – Theory of Evolution – “On the Origin of Species” book

The 5 year voyage of the HMS Beagle Surveying and charting coasts

Antibiotic resistance is enhanced by natural selection The top section represents a population of bacteria before exposure to an antibiotic. The middle section shows the population directly after exposure, the phase in which selection took place. The last section shows the distribution of resistance in a new generation of bacteria. The legend indicates the resistance levels of individuals.

Variations Variation is one of the most critical aspects of species survival. It may be:   a genetic (cellular code) modification   a behavioral tendency This enables some individuals within a species to survive, while others, will perish.

Genetic Variability Species of Side-blotched lizards (Uta stansburiana) in central California Species of Side-blotched lizards (Uta stansburiana) in central California

Give it a TRY – Page 27 Survey the class and find how many people: Survey the class and find how many people: a) Can or cannot bend their thumb joint “backward” without adding pressure b) Have earlobes that are attached or separate c) Have a pointed or smooth hairline Draw a data table to record your results. Create a graph that will best illustrate your results

Inheritance Transmission of characteristics from parents to offspring The characteristics of the parents are carried to the next generation by the process of heredity The characteristics of the parents are carried to the next generation by the process of heredity

What are Non-Heritable Traits? Characteristics are acquired and not necessarily passed on from generation to generation. Athleticism, artistic ability, leadership qualities are all learned during the early years of life.

Continuous Variation Variations are differences in characteristics that have a multitude of variations, such as height, shoe size, arm length etc… Variations are differences in characteristics that have a multitude of variations, such as height, shoe size, arm length etc…

Discrete Variations Discrete variations are differences in characteristics that have a definite form. Discrete variations are differences in characteristics that have a definite form. One characteristic, or the single, other variation, of the characteristic. One characteristic, or the single, other variation, of the characteristic. Either the organism has a trait or it does not. Either the organism has a trait or it does not. Example: Either your earlobes are attached or they are not.

Variation and the Environment Some variations may be influenced by interactions with the environment. These variations are not inherited. Examples include: Change in the pigmentation of skin color throughout the seasons due to the sun. Height and weight can be influenced by diet.

Give it a TRY – Page 29 Ready…………..set…………GO!!!! Ready…………..set…………GO!!!! Quickly clasp your hands together above your head, interlocking your fingers. Look to see which thumb is on top. Note which way feels more natural. Finish the chart in your notes, indicating Left Thumb on Top vs. Right Thumb on Top Decide whether the data is discrete or continuous. Explain your answer.

Is it Discrete or Continuous? Page 29 ActionRight Preference Left Preference Type (circle one) Clasping Hands Continuous Discrete Folding ArmsContinuous Discrete

Sample Multiple Choice Questions Q1. To better understand variation; scientists explore the characteristics, which are passed on from generation to generation within a species. Those characteristics that are passed on from generation to generation are … A. genetic B. inherited C. non-inherited D. non-genetic

Sample Multiple Choice Questions Q2. An albino kangaroo is a kangaroo that is pure white. This characteristic is classified as a … A. non-inherited variation B. continuous variation C. discrete variation D. singular variation

Sample Multiple Choice Questions Q3. Variations caused by interactions with the environment are not heritable. Plants that are grown in dim lighting conditions would turn out to be … A. identical to their parents in all aspects B. much like their parents C. very different from their parents D. similar to parent plants that were grown in dim light

Sample Multiple Choice Questions Q4. Cats B and C are similar in size, but cat A is taller when standing. Like humans, cats pass down genetic information for height, but cats can mature to be a wide range of heights - it is not an "either/or" characteristic. The characteristic of height in cats can be described as a Q4. Cats B and C are similar in size, but cat A is taller when standing. Like humans, cats pass down genetic information for height, but cats can mature to be a wide range of heights - it is not an "either/or" characteristic. The characteristic of height in cats can be described as a A. non-heritable and continuous in variation A. non-heritable and continuous in variation B. heritable and discrete in variation B. heritable and discrete in variation C. heritable and continuous in variation D. non-heritable and discrete in variation D. non-heritable and discrete in variation

Answers to Previous Questions 1. B 2. C 3. D 4. C

Did you … … identify the role of variation in species survival under changing environmental conditions? … describe examples of variation of characteristics within a species, and identify examples of both discrete and continuous variation? … distinguish those characteristics that are heritable from those that are not heritable, and identify characteristics for which heredity and environment may both play a role?

Homework Read pages 20-24, Read pages 20-24, Check and Reflect page 29, #1- 2, #5 Check and Reflect page 29, #1- 2, #5 Update Portfolio Update Portfolio Read pages Read pages 30-36

Question 1 Give one example of a heritable characteristic and one example of a non- heritable characteristic that we did not discuss in class. Give one example of a heritable characteristic and one example of a non- heritable characteristic that we did not discuss in class. Heritable __________________________________ Non-Heritable __________________________________

Question #2 What is discrete variation? __________________________________ __________________________________ __________________________________ What is discrete variation? __________________________________ __________________________________ __________________________________ What is continuous variation? __________________________________ __________________________________ __________________________________ What is continuous variation? __________________________________ __________________________________ __________________________________

Question #5 A scientist wants to study continuous variation in a mouse population. What mouse characteristics would she or he investigate? __________________________________ __________________________________ __________________________________ __________________________________ __________________________________ __________________________________ A scientist wants to study continuous variation in a mouse population. What mouse characteristics would she or he investigate? __________________________________ __________________________________ __________________________________ __________________________________ __________________________________ __________________________________