PEOPLE AND EARTH’S ECOSYSTEM COURSE DESCRIPTION This course explores the ways in which human activity impacts the natural environment and how modification of environment can eventually have significant consequences for human activity. Topics include environmental challenges, such as air and water pollution, population growth and distribution, global atmospheric changes, ecosystems and evolution, agriculture and food resources, and renewable and nonrenewable energy resources. This course will examine the origin, use, impacts and by product of food, water, energy, and mineral resource consumption. Course material will focus on the science and technology associated with Earth’s resources, but will consider the economic, management, and political challenges associated resource use and future sustainability. Module 1: SCIENCE AND THE ART OF GEOGRAPHY ECOSYSTEM OBJECTIVES: At the end of this unit, the students shall be able to: Describe the principles of the ecosystem; and Distinguish the different terrestrial biomes. SIMPLE RECALL What is ecology? And how it differs to the following terms like community and ecosystem? What are the levels of organization? ECOLOGY was derived from the Greek oikos meaning household and logos meaning science or the "study of the household of nature.“ A community includes all populations, representing multiple species, in the same region. An ecosystem is the biotic, or living, community plus the abiotic, or nonliving, environment. Levels of Organization Description? HABITAT VS NICHE BUIOMES OBJECTIVES Describe biomes Identify the characteristics of different types of biomes TERRESTRIAL BIOMES Terrestrial biomes are ecosystems with distinctive communities of life and is found in land. Different biomes exist because of the variations of light, temperature, and moisture across the biosphere. Temperature and moisture are the main factors that determine the dominant plants in each location. BIOME: TEMPERATE RAINFOREST Temperate rainforest is also called temperate coniferous forest. Temperate rainforests are found near the cooler coastal areas further north or south of the equator. It has mild winters, cool summers, and not rainy as tropical rainforest. They are common in coastal areas that have mild winters and heavy rain. Life includes large evergreens, amphibians, mammals, and fish. BIOME: TROPICAL RAINFOREST Tropical rainforests are found closer to the equator where it is warm and where rainfall is abundant and dry season lasts no more than a few months. It is warm and wet. This is characterized with lush jungles and has the greatest diversity of species of all communities. ACTIVITY: GALLERY WALK Instruction: Construct a diorama that significantly shows the characteristics of each biome. An “envoy” should master his/her assigned topic. The students shall take note based on the guide questions below What is the name of a biome? What are the characteristics of this biome in terms of climate, temperature, animals and vegetation present? What are the characteristics of plant and animal adaptations? ACTIVITY: GALLERY WALK BIOMES CHARACTERISTICS of the BIOME G2: Taiga G3: Temperate deciduous Forest G1: Tundra G7: Tropical Savanna ANIMAL /PLANT ADAPTATIONS G4: Temperate Grassland G5: Chaparral G6: Dessert CRITERIA FOR DIORAMA ¼ sheet of yp VISUAL IMPACT and CRAFTSMANSHIP (Attractiveness and how it is done?) CREATIVITY AND RESOURCEFULLNESS (cheapness and availability of materials used) PRESENTER’S PERFORMANCE RATING = 25 pts. = 25 pts. = 50 pts. TOTAL: 100 PTS MODULE 2 THE HUMAN POPULATION MODULE 2: PEOPLE AND POPULATION OBJECTIVES: After successful completion of this module, you should be able to: 1. trace the ancestry of humans. 2. identify the major/most important achievements of human evolution. 3. link evolution and population growth. 4. explain how populations increase and decrease in size; and 5. enumerate causes and issues related to inflation of human population. MODULE 2: PEOPLE AND POPULATION HUMAN EVOLUTION is the evolutionary process that began from the evolutionary history of primates of genus Homo and eventually to the emergence of anatomically modern humans. POPULATION is all the organisms of the same species that live in a particular geographical area. ANTOMICAL CHANGES 1.) BIPEDALISM - It is a major type of adaptive locomotion involving movement on two feet. - Bipedalism is the basic adaptation of the hominid. It is considered to be the main cause of skeletal changes. Theories why evolution favored the adaptation of bipedalism: liberated the hands for reaching and carrying food. saved energy during movement. enabled running and hunting for long distances. enhanced the field of vision; and helped avoid hyperthermia because it reduced the surface area exposed to direct sun. Skeletal changes brought by the evolution of bipedalism: a. b. femur evolved into a slightly more angular position to shift the center of gravity toward the geometric center of the body. knee and ankle joints became increasingly robust to support weight better. Skeletal changes brought by the evolution of bipedalism: human vertebral column became Sshaped and the lumbar vertebrae . The number and size of the lumbar vertebrae in humans is different than in apes. Humans usually have 5 comparatively larger lumbar vertebrae. Most large apes typically have 4 lumbar vertebrae that are relatively smaller than human lumbar vertebrae. b. The lumbar curvature (shown in the red box) permits the hipds and tunk to swivel forward during walking. a. In most quadrupedal hominins, the center of gravity is located near center on the torso. In modern humans, the center of gravity is closer to the center of the pelvis. Skeletal changes brought by the evolution of bipedalism: d. big toe moved into alignment with the other toes to help in walking forward. e. arms and forearms shortened relative to the legs making it easier to run. f. foramen magnum migrated under the skull, a more anterior position; and Humans: foramen magnum is positioned centrally Chimpanzee: FM is positioned towards the back of the skull Skeletal changes brought by the evolution of bipedalism: g. The pelvic region: the long downward facing iliac blade was shortened and widened to keep the center of gravity stable while walking. This made the birth canal smaller and had significant effects on the process of human birth. The smaller birth canal limits the brain size it can accommodate to get out. This prompted to give birth to a relatively immature human offspring when compared to other primates. Brain growth increases after birth, nurtured by the mother. ANTOMICAL CHANGES 2.) ENCEPHALIZATION - process of increasing the complexity of the size of the brain. The human species developed a much larger brain than that of other primates. Because of its size, it enabled social learning and language acquisition in young humans. The temporal lobes that contain centers for language processing and the prefrontal cortex that has been related to complex decision-making and moderating social behavior have increased in size. Encephalization has been tied to consumption of meat and starches and the development of cooking. There is also a theory that intelligence increased as a response to the need of solving social problems. LOBES OF THE BRAIN AND THEIR FUNCTION Image ource: ResearchGate ANTOMICAL CHANGES 3.) SEXUAL DIMORPHISM Sexual dimorphism Sexual dimorphism is the systematic difference in size or appearance of different sex in the same species. For example, in some species, including many mammals, the male is larger than the female. In others, such as some spiders, the female is larger than the male. There is reduced degree of sexual dimorphism in humans. These have been interpreted as a result of increased emphasis on pair bonding for prolonged child-rearing. An important physiological change related to sexuality in humans was the evolution of hidden estrus. This means that female humans are fertile year-round. EXAMPLES OF HIGH SEXUAL DIMORPHISM Males exhibit a more vibrant coloration on their faces and behinds. There's even a noticeable difference between males in the same group, with the dominant adult male exhibiting the brightest red. EXAMPLES OF HIGH SEXUAL DIMORPHISM The bold orange tips found on the forewings of the males makes them unmistakable. Females, allwhite with black wingtips, are less colorful, though both sexes exhibit a similar mottled green appearance with wings closed. This helps trick predators into thinking they're just fallen leaves. 2. ANTOMICAL CHANGES 4.) ULNAR OPPOSITION The ulnar opposition is the contact between the thumb and the tip of the little finger of the same hand. This feature is unique to the genus Homo. This trait facilitates the precision grip and power grip of the human hand, underlying all the skilled manipulations.. OTHER CHANGES a) increased importance on vision rather than smell. b) longer developmental period for the young. c) higher infant dependency. d) a smaller gut. e) faster basal metabolism. f) loss of body hair. g) evolution of sweat glands. h) change in the shape of the dental arcade from being u-shaped to being parabolic. i) development of a chin (found in Homo sapiens alone). j) development of styloid processes; and k) development of a descended larynx. RECENT HUMAN ANCESTRY A.) Gracile Australopithecines • small braincases (400 to 500 cc) • walked on two legs • female 1 meter tall • males 1.5 meter EXAMPLES SEE THE IMAGE - AUSTRALIPITHICUS AFRICANUS Australopithecus africanus was once considered a “killer ape.” They were sometimes eaten by predators. Living together in groups helped these early humans to protect themselves. a rounder cranium housing a larger brain and smaller teeth, but it also had some ape-like features AUSTRALIPITHICUS AFARENSIS one of the longest-lived and best-known early human species—paleoanthropologists have uncovered remains from more than 300 individuals Similar to chimpanzees, Au. afarensis children grew rapidly after birth and reached adulthood earlier than modern humans. They also had small canine teeth like all other early humans, and a body that stood on two legs and regularly walked upright. AUSTRALIPITHICUS ANAMENSIS Australopithecus anamensis has a combination of traits found in both apes and humans. The upper end of the tibia (shin bone) shows an expanded area of bone and a human-like orientation of the ankle joint, indicative of regular bipedal walking AUSTRALIPITHICUS ANAMENSIS They have long forearms and features of the wrist bones suggest these individuals probably climbed trees as well. AUSTRALIPITHICUS RAMIDUS - The pelvis, reconstructed from a crushed specimen, is said to show adaptations that combine tree-climbing and bipedal activity. - scientists announced a partial skeleton, nicknamed ‘Ardi’. - Ardi’s fossils were found alongside faunal remains indicating she lived in a wooded environment. This contradicts the open savanna theory for the origin of bipedalism, which states that humans learned to walk upright as climates became drier and environments became more open and grassy. RECENT HUMAN ANCESTRY C.) Archaic humans, Genus Homo • all African • Homo habilis • 600 cc brain • teeth and jaws smaller than in Australopithecus • taller • less sexually dimorphic in size RECENT HUMAN ANCESTRY RECENT HUMAN ANCESTRY Homo Neanderthalensis the large middle part of the face, angled cheek bones, and a huge nose for humidifying and warming cold, dry air. Their bodies were shorter and stockier than ours, another adaptation to living in cold environments RECENT HUMAN ANCESTRY RECENT HUMAN ANCESTRY B.) Robust Australopithecines • small brained • larger than gracile Australopithecus • large bony crest • Jaw muscle attachments EXAMPLES SEE THE IMAGE MODERN HUMANS Last 100,000 years Biggest brain 2000 cc Cro-Magnon Today, about 1200 cc Higher foreheads Flatter faces with prominent nose Culture: • Cro-Magnon, 1 found buried in grave with 2 men, 1 woman, and infant • Animal bones, jewelry, stone tools THE LAST SURVIVOR Modern Homo sapiens descended from multispecies radiation of African hominids ( the group consisting of all modern and extinct Great Apes). Many species co-existed at one time (estimated to be at least 5 species). Current evidence of human evolution suggests that there was interbreeding with other hominins (term given to humans and all of our extinct bipedal ancestors), suggesting that the path was weblike and non-linear. THE LAST SURVIVOR How and where did modern humans arise? - Archaic humans were certainly in Africa.
