Topic 5.2:  Natural Selection

Essential Idea:   The diversity of life has evolved and continues to evolve by natural selection.

At SHS, Topic 5.2 is taught in the following class unit(s):

• Natural Selection (unit 19)
• Evidence for Evolution (unit 20)

Statements & Objectives:

5.2.U1  Natural selection can only occur if there is variation among members of the same species.

• Define variation.
• Explain why natural selection can only function if there is variation in a species.

5.2.U2  Mutation, meiosis and sexual reproduction cause variation between individuals in a species.

• List sources of genetic variation.

5.2.U3  Adaptations are characteristics that make an individual suited to its environment and way of life.

• Define adaptation.
• List examples of adaptations.

5.2.U4  Species tend to produce more offspring than the environment can support.​

• Use an example to illustrate the potential for overproduction of offspring in a population.​
• State that species have the ability to produce more offspring than the environment can support.

5.2.U5  Individuals that are better adapted tend to survive and produce more offspring while the less well adapted tend to die or produce fewer offspring.​

• Outline how a “selective pressure” acts on the variation in a population.
• List examples of “selective pressures.”
• Explain the effect of the selective pressure on the more and less adapted individuals in a population.

5.2.U6  Individuals that reproduce pass on characteristics to their offspring.​

• Contrast acquired characteristics with inheritable characteristics.
• State that only inherited characteristics can be acted upon by natural selection.

5.2.U7  Natural selection increases the frequency of characteristics that make individuals better adapted and decreases the frequency of other characteristics leading to changes within the species.

• Compare the reproductive success of better and less well adapted individuals in a population.
• Explain the cause of the change in frequency of traits in a population through natural selection.​. ​

5.2.A1  Changes in beaks of finches on Daphne Major.

• Outline the role of Charles Darwin and Peter and Rosemary Grant in the study of Galapagos finches.
• Explain how natural selection leads to changes in the beaks of Galapagos finches with changes in weather conditions. ​

5.2.A2  Evolution of antibiotic resistance in bacteria.

• Explain how natural selection leads to changes in antibiotic resistance.
• List reasons why evolution of antibiotic resistance has been rapid.
• Outline the effect of not completing a full dose of antibiotics on the development of antibiotic resistance.​ ​

5.2.NOS  Use theories to explain natural phenomena- the theory of evolution by natural selection can explain the development of antibiotic resistance in bacteria.​

• List three trends that have been observed in the development of antibiotic resistance.
• Use a graph to illustrate antibiotic resistance over time.​

In the News:

• Sea Stars Started Dissolving. What Helped Some of Them Survive? (2018-06-08)
• ​The headache of adapting to the cold, literally (2018-05-03)
• Calls to rein in antibiotic use after study shows 65% increase worldwide (2018-03-26)
• With Less Snow, Can Coat-Changing Animals Adapt Quick Enough To Avoid Predators? (2018-02-21)
• The dangerous evolution of HIV (TED talk, posted 2018-01)
• Variation within species is critical aspect of biodiversity (2017-12-05)
• ​Things Looked Bleak Until These Birds Rapidly Evolved Bigger Beaks (2017-11-28)
• As climate warms, mice morph (2017-11-27)
• WHO To Farmers: Stop Giving Your Animals So Many Antibiotics (2017-11-07)
• Yellowstone Grizzlies May Soon Commingle with Northern Cousins (2017-11-03)
• How Kangaroo Rats Escape Rattlesnakes (2017-10-12)
• ​Doctors need a nudge to reduce antibiotic prescriptions, study finds (2017-10-10)
• World's 'better' countries have higher rates of cancer (2017-10-11)
• ​People from Mexico show stunning amount of genetic diversity (2014-06-12)
• Drool makes grass safe to eat (2014-07-22)
• For bats and dolphins, hearing gene prestin adapted for echolocation (2014-08-01)
• A World of Creatures That Hide in the Open (2014-08-18)
• Why some geckos lose their ability to stick to surfaces (2015-01-07)
• ​Stickleback fish adapt their vision in the blink of an eye (2016-05-04)
• Cholera Is Altering the Human Genome (2013-07-03) 
• How the whale became the whale (2013-11-24)
• How Farming Reshaped Our Genomes (2014-01-26)
• Black Death Left a Mark on Human Genome (2014-02-03)
• Humans Spread Mutation That Smoothes a Horse's Ride (2014-02-07)
• Evolution sparks silence of the crickets (2014-05-29)
• Sexual arms race gave male beetles sticky feet (2014-06-10)
• Origins of Arctic fox traced back to Tibet (2014-06-11)
• Spread of Artemisinin Resistance in Plasmodium falciparum Malaria (2014-07-31)
• Rapidly Evolving Feet Do Not Fail Lizard Species (2014-10-23)
• Hybrid 'super mosquito' resistant to insecticide-treated bed nets (2015-01-12)
• Scientists discover organism that hasn't evolved in more than 2 billion years (2015-02-03)
• Researchers reveal how hearing evolved (2015-02-06)
• Arsenic Antidote Hidden In Our Genes (2015-03-05)
• How Europeans evolved white skin (2015-04-02)
• Did natural selection make the Dutch the tallest people on the planet? (2015-04-07)
• Evolutionary clock ticks for snowshoe hares facing climate change (2016-01-22)
• Unravelling the secret of antibiotic resistance (2016-03-22)
• Prairie dogs reap rewards from being cold-blooded killers (2016-03-22)
• ​Study spots evolution in action in Florida bird (2016-05-20)
• ​‘Landmark study’ solves mystery behind classic evolution story (2016-06-01)
• Carp undergo ‘reverse evolution’ to get their scales back (2016-08-23)
• Lice No Longer Stopped by Common Drugstore Remedies (2016-09)
• How natural selection acted on one penguin species over the past quarter century (2016-09-24)
• Rapid Evolution Saved This Fish From Pollution, Study Says (2016-12-09)
• Climate shaped the human nose, researchers say (2017-03-17)
• Dramatic evolution within human genome may have been caused by malaria parasite (2017-03-23)
• How to make a cave fish in just a few thousand years (2017-04-03)
• Fishing can lead to rapid evolutionary changes in exploited fish populations (2017-05-16)
• How whales became the biggest animals on the planet (2017-05-24)
• They Were Shorter and at Risk for Arthritis, but They Survived an Ice Age (2017-07-06)
• Massive genetic study shows how humans are evolving (2017-09-06)
• In Darwin’s Footsteps (2014-08-04)
• Darwin’s iconic finches join genome club (2015-02-11)
• A gene that shaped the evolution of Darwin's finches (2015-02-11)
• Evolution of Darwin’s finches tracked at genetic level (2016-04-21)
• Watching Evolution Happen in Two Lifetimes (2016-09-22)
• Antibiotic Use On The Farm: Are We Flying Blind? (2013-08-29)
• Genomes reveal roots of TB drug resistance (2013-09-01)
• CDC issues report on controlling antibiotic resistance (2013-09-16)
• If Chosen Wisely, Existing Drugs Fight Resistant Bugs (2013-09-25)
• Antibiotics Can't Keep Up With 'Nightmare' Superbugs (2013-10-22)
• Despite Many Warnings, Antibiotics Are Still Overprescribed (2013-10-04)
• Are Farm Veterinarians Pushing Too Many Antibiotics? (2013-11-01)
• Drug Companies Accept FDA Plan To Phase Out Some Animal Antibiotic Uses (2013-12-11)
• Russia's drug-resistant TB spreading more easily (2014-01-26)
• MRSA spreads in households (2014-04-21)
• First Global Drug Resistance Overview Paints Grim Picture (2014-04-30)
• Last-Resort Antibiotics In Jeopardy As Use Rises Globally (2014-07-09)
• Antibiotic resistant bacteria video (2014-08)
• Battling superbugs: Two new technologies could enable novel strategies for combating drug-resistant bacteria (2014-09-21)
• Old drug may be key to new antibiotics (2014-09-22)
• Antibiotics, bacteria, resistance genes found in dust from feedlots (2015-01-22)
• Drug-resistant typhoid fever becoming an epidemic in Africa and Asia (2015-05-11)
• She's Got One Of The Toughest Diseases To Cure. And She's Hopeful (2015-05-20)
• Spread of antibiotic-resistance gene does not spell bacterial apocalypse — yet (2015-12-21)
• Testing the evolution of resistance by experiment (2016-03-03)
• Prevalence of Inappropriate Antibiotic Prescriptions Among US Ambulatory Care Visits, 2010-2011 (2016-05-03)
• Gonorrhea Is Becoming Untreatable, U.N. Health Officials Warn (2016-08-30)
• FDA Bans Sale of Many Antibacterial Soaps (2016-09-02)
• Watch as Bacteria Evolve Antibiotic Resistance in a Gigantic Petri Dish (2016-09-07)
• Increase in Antibiotic-Resistant Bacteria Hinders Treatment of Kidney Infections (2016-09-16)
• Antimicrobial Resistance (2016-09-20)
• U.N. To Take On Antibiotic Resistance At General Assembly (2016-09-18)
• Despite Pledges To Cut Back, Farms Are Still Using Antibiotics (2016-12-22)
• The drug-resistant bacteria that pose the greatest health threats (2017-02-28)
• Almost untreatable superbug CPE poses serious threat to patients, doctors warn (2017-04-17)
• Resistance to last-ditch antibiotic has spread farther than anticipated (2017-06-12)
• Untreatable gonorrhoea on the rise worldwide (2017-07-07)
• Are antibiotics turning livestock into superbug factories? (2017-09-28)