This lesson will increase your knowledge of concepts covered in the following TEKS for biology:

This lesson will increase your knowledge of concepts covered in the following TEKS for biology: 3.a – Analyze, review, and critique scientific explanations, including hypotheses and theories, as to their strengths and weaknesses using scientific evidence and information 3.c – Evaluate impact of research on scientific thought, society, and the environment 6.c – Identify and illustrate how changes in DNA cause mutations and evaluate the significance of these changes 6.d – Compare genetic variations observed in plants and animals 9.b – Compare the energy flow in photosynthesis to the energy flow in cellular respiration

This lesson will increase your knowledge of concepts covered in the following TEKS for biology: 9.d – Analyze the flow of matter and energy through different trophic levels and between organisms and the physical environment 12.a – Analyze the flow of energy through various cycles including the carbon, oxygen, nitrogen and water cycles 12.d – Identify and illustrate that long-term survival of species is dependent on resource space and may be limited 12.e – Investigate and explain interactions in an ecosystem including food chains, food webs, and food pyramids 13.a – Evaluate the significance of structural and physiological adaptations of plants to their environment

Previous Lesson Origin and Evolution of Life

Question: According to scientists, what are the ages of the following events? • Homo sapiens arise • Lucy • Evolution of life on earth • Life first appears on earth • Earth formed • Universe formed

Evolutionary Times Years Before Present 0.13 million Homo sapiens arise 3-4 million Lucy present 3.5 billion to present Evolution of all forms of life 3.5 billion Earliest known fossil bacteria 4.5 billion Formation of Earth 13.7 billion Origin of the universe

Question: After the Industrial Revolution in England, the tree bark changed from light to dark and the moth populations changed from predominantly light to dark. How would evolutionary theory explain this? After pollution: 80% dark-colored phenotype Original population: 10% dark-colored phenotype Based on: Campbell, et al., Biology: Concepts & Connections, Benjamin Cummings

Evolution • Change in the genetic makeup of a population through time, sometimes leading to formation of new species • Natural selection by the environment determines which organisms will survive and reproduce • Natural selection (bird predation) favored dark moths after the trees became dark

Today’s Lesson Agricultural Systems and Transgenic Organisms

Overview of Lesson • Humans before agriculture • Domestication and agriculture • Energy flow in agricultural systems • Productivity and technology • Genetic engineering

Out of Africa Theory: Our human ancestors evolved in Africa and then spread around the world Based on: Diamond, J., Guns, Germs and Steel, Random House, 1997.

12,000 years ago, humans (Homo sapiens) were widely distributed Based on: Smithsonian, October 1986

12,000 years ago, agricultural systems did not exist and humans (Homo sapiens) were hunter-gatherers Based on: Smithsonian, October 1986

Humans used tools such as needles, spears and clothes, and livedin small groups Based on: Smithsonian, October 1986

What made it possible to change from small groups to the large cities of today? Photo courtesy of Texas Department of Transportation 10,000 BC Today

Large cities and highly advanced civilizations were only possible after we domesticated wild plants and animals and developed agricultural systems Photo courtesy of Texas Department of Transportation

Overview of Lesson • Prehistoric humans • Domestication and agriculture • Energy flow in agricultural systems • Productivity and technology • Genetic engineering

Domestication Domestication process began about 12,000 years ago A domesticated plant or animal is modified from its wild ancestors for use by humans

Early domestication was unintentional: seeds brought back by hunter-gatherers foraging in the wild grew by accident in latrines and garbage dumps Later domestication was conscious: scientists planted many different seeds, selected the best progeny and planted their seeds

Changes in wheat through domestication Wild form Based on: Scientific American, September 13, 1976

Dates (BC) and Places of First Evidence for Domesticationfrom Diamond, J., Guns, Germs and Steel, Random House, 1997 Dog 10,000 BC SW. Asia,China, North America Sheep 8,000 BC SW. Asia Goat 8,000 BC SW. Asia Pig 8,000 BC China, SW. Asia Cow 6,000 BC SW. Asia, India, North Africa Horse 4,000 BC Ukraine Donkey 4,000 BC Egypt

Dates (BC) and Places of First Evidence for Domesticationfrom Diamond, J., Guns, Germs and Steel, Random House, 1997 Wheat, Pea, Olive 8,500 BC SW. Asia Rice, Millet 7,500 BC China Sorghum 5,000 BC Sahel Corn, Beans, Squash 3,500 BC Mesoamerica Potato 3,500 BC Andes Sunflower 2,500 BC Eastern U.S.

Movement of agricultural cropsfrom the Fertile Crescent From: New York Times, November 18, 1997

Highly advanced civilizations were present by 2,000 - 4,000 BC Based on: National Geographic, September, 1998

There are two types of agricultural systems that make the energy of the sun available as food to humans Photos courtesy of Texas Department of Transportation Sun Grass Herbivore Man Sun Grain Crop Man

All agricultural systems are based on plants converting the energy of the sun to the energy of sugar through the process of photosynthesis energy of the sun + carbon dioxide + water energy of sugar + oxygen

Electromagnetic Spectrum Based on: Campbell, et al., Biology: Concepts & Connections, Benjamin Cummings

Energy is lost due to respiration of plants and animals energy of sugar + oxygen energy of ATP + carbon dioxide + water Energy of ATP is then used to stay alive

Relationship between photosynthesis and cellular respiration Photosynthesis Respiration Based on: Campbell et al., Biology: Concepts and Connections, Benjamin Cummings

Energy flow in two types of agricultural systems Based on: Scientific American, September 1976

Growth in Agricultural Productivity From: : Scientific American, February, 1983

Harvesting Technology Photos courtesy of Texas Department of Transportation

Irrigation Technology Based on: Scientific American, February 1983 Photos courtesy of Texas Department of Transportation

PesticideTechnology DomesticationTechnology Photo courtesy of Texas Parks and Wildlife Department Photo courtesy of Texas Department of Transportation

Fertilizer Technology

Despite Technology, Chronic Under-nutrition is Still a Worldwide Problem

Genetic Engineering Take a gene (directing synthesis of a desired protein) from an animal or plant and insert it into an agricultural plant The engineered agricultural plant makes the protein specified by the inserted gene. Large quantities of the protein can be produced by growing large crops of the engineered plant

From: Time, May 26, 2003 Agricultural plants have been modified to contain human genes to produce human proteins to fight human disease

From: Time, May 26, 2003 Many agricultural plants are undergoing genetic engineering to fight pests

Critics have named crops with human genes “Pharmageddon.” Environmentalists are worried that unnaturally combined genes may spread like “genetic kudzu.”Foods with unnatural proteins are called “Frankenfood.” People are worried about buying foods in the grocery store that are genetically engineered to produce their own pesticides. From: Time, November 29, 1999

This corn contained a protein that provides resistance to pests and was only approved for animal foods

2005 GM strain contaminating traditional canola Canada, Australia • 2009 GM genes escape to wild corn Mexico • 2009 crops tested for GM cross contamination in Australia • 2009 Mass GM corn crop failure in South Africa

Next LessonPesticides and Organic Farming

This lesson will increase your knowledge of concepts covered in the following TEKS for biology: