Evolution and Adaptation

• Biological organisms must adapt to their environment to survive.

Evolution and Adaptation

• Adaptation is any structure, behavior, or internal process that allows response to a stimulus and increases survival chances for an organism.
• Evolution is the gradual accumulation of adaptations over time.

Polar Bear Adaptations

• White fur provides camouflage against ice.
• A thick fat layer under the skin aids thermoregulation.
• Long, stiff hair between foot pads protects from the cold and prevents slipping on ice.
• Polar bears are strong swimmers.
• Hollow fur traps air for buoyancy and insulation.
• Small, rounded ears prevent water from entering and freezing eardrums.

Charles Darwin's Contributions (1859)

• Natural selection is the process where better-suited individuals survive and reproduce successfully.
• Descent with modification is the concept that each living species has descended with changes causing organisms to occupy different niches.

Response and Homeostasis

• All organisms can respond to their environment.
• Stimulus is any environmental condition requiring an adjustment by an organism.
• Response is the reaction to a stimulus.
• Homeostasis is the maintenance of stable internal conditions like body temperature and water content.

Organization

• All living things are organized into cells.

Types of Organism by Cell Organization

• Unicellular organisms are made of one cell, such as Streptococcus pyogenes.
• Multicellular organisms are made of more than one cell; differentiated cells have different functions.

Energy

• All organisms use energy to grow, respond, maintain homeostasis, and adapt.
• Metabolism is described as the chemical process by which life uses food, water, etc., to make energy.

Categories of Living Things According to Food Source

• Autotrophs use energy from the sun via photosynthesis to make their own food.
• Heterotrophs ingest food to receive energy.

Reproduction, Growth, and Development

• All organisms reproduce to create new organisms.
• DNA contains the hereditary material of a cell.
• Growth is increase in more living material.
• Development includes the changes that occurs for an organism in its lifetime.

Interdependence of Organisms

• Ecology is the study of the interaction of organisms with their environment.
• Energy passes from producers (plants) to herbivores to carnivores to decomposers.

Factors Determining Interdependence

• Abiotic factors are non-living things like air, water, energy, soil, temperature, and minerals.
• Biotic factors include all living things on earth.

Theories About the Origin of Life

• Special Creation suggests life-forms were put on earth by divine forces, which is widely accepted and at the core of most religions.
• Extraterrestrial Origin, or panspermia, suggests life infected earth from another planet via meteors or cosmic dust containing organic molecules.
• Spontaneous Origin suggests organisms originated from inanimate objects

Theories About Where Life Started

• At the ocean's edge under the blanket of a reducing atmosphere, life emerged in the early earth’s high-temperature environment.
• Under frozen oceans proposes that life originated under a frozen ocean, which is unlikely based on evidence suggesting the early earth was quite warm.
• Deep in the earth's crust suggests life formed as a by-product of volcanic activity, with iron and nickel sulfide minerals acting as chemical catalysts.
• Within clay says life is the result of silicate surface chemistry, though there's little evidence to confirm this.
• At deep-sea vents hypothesize that life originated at deep-sea hydrothermal vents, with prebiotic molecules synthesized on metal sulfides.

Miller-Urey Experiment

• The Miller-Urey experiment attempted to identify what organic molecules might have been produced on early Earth, which introduced prebiotic chemistry.
• The Miller-Urey experiment involved assembling a reducing atmosphere rich in hydrogen and excluding gaseous oxygen

Miller-Urey Experiment steps:

• Place this reducing atmosphere over water.
• Maintain the mixture at under 100°C
• Simulate lightning with sparks.
• Within a week, 15% of the carbon originally present as methane gas had converted into formaldehyde, hydrogen cyanide, formic acid, urea, glycine and alanine.

The Bubble Theories

• Bubbles may have played a key role in the evolution of cells, especially at the ocean's edge.
• Alexander Oparin's “primary abiogenesis” the first bubble theory is based on the fact that all living cells come from previous living ones.
• Oparin suggested that the present day-atmosphere was incompatible with the creation of life
• Oparin believed life must have arisen from non-living matter, and cells concentrate materials within themselves by means of a cell membrane
• Oparin called those bubble-like structures protobionts.
• Louis Lerman proposed that chemical processes that led to the evolution of life took place within ocean bubbles based on the cycle: Volcanoes release gases enclosed in bubbles > the gases reacted to produce molecular compounds > the bubbles reach the surface where heat radiation and other energy forms combine with the molecules > complex molecules fall into the sea, enclose into bubbles.

Other Terms for Bubbles

• Microspheres
• Protocells
• Protobionts
• Micelles
• Liposomes
• Coacervates

Microfossils

• Earliest evidence of life
• Fossils of microscopic life, 3.5 billion years old
• Small (1-2 micrometers)
• Single-celled
• Lack appendages and have little evidence of internal structure
• Resemble prokaryotes
• Eukaryotes did not appear until 1.5 billion years ago.

Archaebacteria

• First major group of bacteria.
• The word archaebacteria came from the Greek word meaning “ancient ones".
• Are the surviving representative of the first ages of life on earth.
• Can be found in depths of the Black Sea or the boiling waters of hot springs and the deep sea vents.
• Bacteria living in very high temperatures without oxygen or anaerobically.
• Archaebacteria lack peptidoglycan in their cell walls.

Archaebacteria Types

• First to be studied: methanogens among the most primitive that exist today.
• Can live in salty environments like extreme halophiles or hot environments such as extreme thermophiles.

Eubacteria

• Second major group of bacteria with very strong cell walls and a simpler gene architecture
• Cyanobacteria contains chlorophyll similar to plants and algae.
• Cyanobacteria produce oxygen and played a role in increasing the Earth's oxygen level.

Coastal Hazards - Erosion

• Occurs due to destructive waves wearing away the coast.

Coastal Hazards - Accretion

• A gradual increase of land due to sedimentation.

Coastal Hazard Waves

• Generated by offshore winds and sometimes are thousands of kilometers from where they reach the shoreline.

Coastal Hazard Rogue Waves

• Extremely dangerous that can reach a height of 100 ft.

Coastal Hazards - Sea Level Change

• Caused by processes that operate locally and affect oceans.
• Eustatic sea level is known as global sea level, and contributes in coastal erosion.
• Relative sea level is the sea position influenced by both land and water movement.

Coastal Hazards - Storm Surge

• A local rise in sea level caused by wind from storms.
• Increased wind and lower atmosphere are cyclone causes.
• Is a continued sea level rise, not water advancing

Coastal Hazards - Saltwater Intrusion:

• The induced flow of saltwater into freshwater aquifers caused by groundwater over-pumping.
• Groundwater consists of surface water and source water in springs and wells
• Aquifers geological formations of groundwater, that naturally replenished by rain.
• Saltwater intrusion occurs when groundwater levels in aquifers deplete faster than recharge.
• This causes dispersion, the result of freshwater contamination resulting with saline material.
• This causes a limited drinkable water supply, and reduction in agriculture.

Mitigation and Adaptation of Coastal Hazards

• Governmental agencies are responsible for evacuation plan and shelters
• Relocation and education are also preventative measures.

Hydrometeorological Hazards

• Are atmospheric, hydrological, or oceanographic in nature.

Types of Hydrometeorological Hazards

• Cyclones
• Greek meaning: coil of snake
• Area or center of low atmospheric pressure, rotating winds
• Tropical Cyclones
• from warm tropical ocean water, typically between 5° to 20° latitude
• Extratropical Cyclones
• Develop over land or water, temperate regions, between 30° and 70° latitude
• Cyclone intensity
• Is indicated by the cyclone's sustained wind speeds and lowest atmospheric pressure

Terminology for Strong Tropical Cyclones

• Hurricanes occur in Atlantic and Pacific Oceans.
• Derived from a Caribbean reference.
• Typhoons occur in the Pacific Ocean west of the International Dateline.
  • Derived from a Chinese reference.
• Tropical cyclones
  • Are general term for thunderstorm complexes rotating around an area of low pressure
• Low-intensity cyclones are termed tropical depressions and storms
• High-intensity cyclones are hurricanes/typhoon

Tropical Cyclone Formation

• First a tropical disturbance is a large area of unsettled weather that is typically 200 to 600 km in diameter, and has thunderstorms for over 24 hrs.
• A disturbance becomes a depression when winds increase forming a low-pressure center.
• The depression becomes a tropical storm when sustained wind speeds increase to 63 km per hour
• The tropical storm becomes a hurricane/typhoon with increased speed

Tornado Features

• Rainbands are clouds that spiral.
• The eyewall is the innermost band of clouds has the most intense winds

Geological Hazards

• A geological hazard is a natural geologic event that poses a threat to human life.

Geological Hazards - Earthquakes

• Worldwide, people feel an estimated one million earthquakes a year.
• Earthquake the trembling of earth's surface.

Earthquake Features

• Epicenter is the Earth’s surface above the original fault rupture
• Focus is the location of the initial breaking or rupturing
• Hypocenter – directly below the focus
• Earthquakes are measured and compared by intensity and magnitude.
• Moment magnitude indicates the size of earthquake with a decimal number

Richter Scale

• Developed by Charles Richter
• Used by news reporters

Effects of Earthquakes and Natural Hazard Linkages

• Shaking and ground rupture are the immediate effects of a catastrophic earthquake with violent shaking accompanied by wide-spread surface rupture and displacement.
• Liquefaction earthquakes can cause near-surface layer of water-saturated sand to change rapidly from solid to a liquid
• Earthquake that shifts land can cause groundwater levels to increase or decrease.
• Earthquakes can cause landslides
• Shaking can break electrical power and gas lines resulting in fires.
• Diseases are caused by loss of sanitation and housing, contaminated water supplies.

Landslide

• A downslope movement of rock, debris, earth, or soil
• Slopes are the inclination of a land surface
• Landslide causes are variable interactions: earth, slope angle, climate, vegetation, and time

Earth Material

• Relates to composition, cementation, and weaknesses

Topography and Slope Angle

• Angle that influences slope.

Climate & Vegetation

• Are a large influence for landslides.

Water

• Can increase or decrease stability.

Time

• Relates to weathering time.

Man-Made Factors of Vulnerability to Landslides Effects of Landslides

• Deforestation, settlement construction, buried pipelines, lack of warning systems, and roads or communication

Volcanoes

• Volcanic activity produced the primordial atmosphere.
• Magma is Molten rock under surface
• Lava is erupted molten rock
• Vent opening of volcano from which volcanic materials are extruded onto surface
• Two-thirds of active volcanoes are located on Pacific’s "Ring of Fire"

"Ring of Fire"

• Has associated tectonic belts comprised of deep oceanic trenches, volcanic arcs, and volcanic belts.
• Active volcanoes are currently erupting
• Dormant volcanoes could become active
• Extinct volcanoes that are unlikely to erupt again.
• Earthquakes, gas emission, or magma can cause eruptions

Geological Hazard Mitigation & Adaptation

• Reduce risks associated with the hazard

Earthquake Hazard Reduction Program

• Government, National Disaster Risk Reduction Council initiatives
• The program aims at understanding quake source, and predicting effects

Personal Protection Against Earthquakes

• Before the quake: prepare your home for earthquakes
• During: drop, cover, and hold
• After: carefully check your surroundings, leaving afterwards.

Soil Mechanics

• Includes the sciences edaphology and pedology.

The Four Spheres & Subsections

• The study of the hydrosphere includes hydrogeology, physical/chemical/biological oceanography.
• Glaciology (cryosphere) relates to the ice and icy surfaces of Earth.
• The study of atmosphere includes meteorology, climatology, atmospheric chemistry and atmospheric physics
• Earth Science field is interdisciplinary

Structure of Earth

• Crust, 8-40 km deep, outermost layer
• Separated from next layer by surface with seismic waves that change velocity or Mohorovičić Discontinuity

Mantle

• The mantle a thick section, can cause convection currents
• Deep mantle: rises/cools/sinks/heats for a cycle. Divided it not 2, upper vs. lower layers because of the transition to the 2 mantle layers.

Core

• The innermost part of earth divided into two parts - solid and liquid core

Origin of Earth

• The Creation Theory is the biblical concept that the universe was said to be created in 7 days.
• The Big Bang Theory suggests that the Universe and Earth formed by cataclysmic explosion in science.

History of Earth

• The Earth was formed, deep within it radioactive elements formed enveloped liquid outer core
• The Earth was formed about 4.5 Billion years ago from debris.
• Volcanic, Earth was molten and frequent collisions occurred
• Solar nebula a disk dust, accretion gas
• Earth slowly began to cool, water condensed by outgassing, and volcanic reactions.
• Continents formed and broke, volcanic eruptions etc reshaped earth
• Rodinia, the old "supercontinent" combined to Pannotia combined Pangea
• Then came present pattern of ice ages, Polar Regions etc.

Continental Drift Theory

• Wegener theorized one Pangea, was once all-earth continents.
• Fossil evidences existed for "continental drift", glossopteris plant species, connecting continents.

Subsystems of earth

• Lithosphere is crust earth - inorganic
• Hydrosphere, the water systems, moisture from air included
• Biosphere, comprised of living things from bacteria> whales
• Atmosphere, air subdivided to layers, gas mixtures.