Final Lecture Exam

Survivorship Curve 1

• High Survivorship til old age

• ex: Turtle and Humans (in developed countries)

Survivorship Curve 2

• Survivorship decreases at a steady regular pace

• ex: Rodents and Adult Birds

Survivorship Curve 3

• High Mortality in the early years of life but those that do survive live long years

• ex: Fish

Carrying Capacity

• The maximum population size an environment can sustain without degrading

• Relates to maximum sustainable yield as it determines the ceiling for resource extraction without harming the ecosystem

Age Pyramids

• Can have 2 shapes: rectangular and triangular shapes

• Rectangular shaped pyramids come from Industrialized countries like Norway due to low birth rates and low death rates in older individuals

• Triangular shaped pyramids come from Developing countries like Kenya due to high birth rates and high death rates in older individuals

Big Bang Reproduction

• Reaches reproductive maturity at one year

• Mates intensely over a 3 week period

• Males usually die shortly after mating period

• Females usually die after their done with breastfeeding their first child

Slow, Gradual Reproductive Investment

• Reaches sexual maturity at one year

• Produces 1 offspring per year

Fast, Intensive Reproductive Investment

• Reaches sexual maturity at one month

• Produces litters of 6 to 10 offspring every month

Exponential Growth

• A type of population growth where the number of individuals increases rapidly over time in an ideal environment with abundant resources (more than a single offspring necessary to replace itself)

• Humans can experience exponential growth under ideal conditions, such as during periods of technological advancement and improved healthcare, leading to lower mortality rates and increased birth rates

Logistical Growth

• A type of population growth where the growth is reduced due to nearing the carrying capacity

• As human populations grow and approach the carrying capacity of their environment, factors such as resource limitations, increased competition, and environmental constraints start to regulate growth. This transition often leads to a stabilization of population numbers, where birth rates may decline as societies develop, reflecting the characteristics of logistical growth

What is unusual about human population growth?

• Rapid growth rates

• Technological Advancements

• How we are able to pack ourselves in environments (High Rise Apartment Buildings)

Density Dependent Limiting Factors

• Intensifies as the population grows in size

• ex: Disease, Competition (like for Food Supply), Predation

Limiting Factors

• Environmental conditions or resources that restrict the growth, abundance, or distribution of a population within an ecosystem

• Can be separated into 2 categories: Density Dependent and Density Independent

Density Independent Limiting Factors

• Affect population size regardless of the population density and can cause drastic changes

• ex: Natural Disaster, Severe Weather, Pollution

Water Cycle

• 1 Evaporation: Water from oceans, lakes, rivers, and plants transforms into water vapor due to solar energy. This process is facilitated by heat, and increased temperatures can enhance evaporation rates.

• 2 Transpiration: Plants absorb water through their roots from the soil and release water vapor through their leaves during photosynthesis. Together with evaporation, this process is often referred to as 'evapotranspiration'

• 3 Condensation: The water vapor rises into the atmosphere where it cools and condenses into tiny droplets, forming clouds. This process is essential for creating precipitation

• 4 Precipitation: When water droplets in clouds combine and grow heavy enough, they fall back to Earth as rain, snow, sleet, or hail, depending on the atmospheric conditions

• 5 Runoff and Infiltration: Precipitated water can either run off into waterways or infiltrate the ground, replenishing groundwater supplies. This process helps in recharging aquifers.

Carbon Cycle

• 1 Photosynthesis: Plants absorb carbon dioxide from the atmosphere during photosynthesis, using sunlight to convert it into glucose and oxygen. This process is the foundation of the food chain, as it provides the energy needed for growth and sustenance of plant life

• 2 Respiration: All living organisms, including plants, animals, and microorganisms, respire by consuming organic matter, releasing carbon dioxide back into the atmosphere as a by-product of metabolism. This process maintains the balance of carbon in the ecosystem

• 3 Decomposition: When plants and animals die, decomposers such as fungi and bacteria break down organic matter, returning carbon to the soil and releasing carbon dioxide back into the atmosphere. This process enriches the soil and supports nutrient cycles

• 4 Fossil Fuels: Over millions of years, preserved organic carbon in the earth has formed fossil fuels (coal, oil, and natural gas). Burning these fossil fuels for energy releases carbon dioxide back into the atmosphere, contributing to global warming

Nitrogen Cycle

• 1 Fixation: Nitrogen gas has a completely unstable chemical structure by most organisms which gets ‘fixed’ by soil dwelling bacteria, producing ammonia and compounds containing nitrogen

• 2 Assimilation: Plants uptake nitrogen from the soil in the form of nitrates and convert it into organic molecules, such as amino acids and proteins. Animals then obtain nitrogen by consuming plants or other animals, integrating it into their biological systems

• 3 Decomposition: When organisms die or excrete waste, nitrogen in organic matter is converted back to ammonia by decomposing bacteria and fungi. This process returns nitrogen to the soil, making it available for nitrification and further assimilation by plants

Tundra

• Located in Arctic regions and high mountain areas

• Extremely cold (Permafrost)

• Limited Vegetation (no trees)

• Low species diversity

• Permafrost (permanently frozen ground) affects soil and plant growth; sensitive to climate change

Boreal Forest

• Located across Canada Alaska, Russia, and Northern Europe

• Cold, with long winters and short summers; moderate rainfall

• Dominated by coniferous trees (e.g., spruce, fir, pine) with some deciduous trees

• Species include moose, wolves, and migratory birds; high adaptation to cold

• Acidic, nutrient-poor soils; significant carbon sink due to the dense forest cover

Temperate Evergreen Forest

• Regions such as Eastern North America, Western Europe, and parts of Asia

• Moderate temperatures with four distinct seasons and average rainfall

• Deciduous trees (e.g., oak, maple) and some coniferous trees

• Diverse wildlife, including deer, bears, and various bird species; some are migratory

• Soils are generally fertile; these ecosystems play vital roles in carbon storage and supporting wildlife

Temperature Deciduous Forest

• Found primarily in regions like Eastern North America (e.g., the Appalachian region), parts of Western Europe, and East Asia (e.g., China, Japan)

• Moderate, with averages ranging from very cold in winter to over very hot in summer (very seasonal)

• Common trees include oaks, maples, beech, hickory, and sweet gum

• A diverse range of animals inhabit these forests, such as white-tailed deer, black bears, raccoons, and numerous bird species

Grassland

• Found in temperate regions such as the Great Plains of North America and the steppes of Eurasia

• Moderate rainfall (250-750 mm per year) with hot summers and cold winters

• Dominated by grasses, with few trees due to insufficient rainfall and lost trees due to farmlands

• Home to large herbivores (e.g., bison, antelope) and predators (e.g., coyotes)

• Fertile soils ideal for agriculture; grassland ecosystems are often converted to farmland, affecting biodiversity

Chaparral

• Found in regions with a Mediterranean climate, primarily along the coasts of California, the Mediterranean Sea, parts of Australia, and Central Chile

• Experiences hot, dry summers and mild, wet winters

• Dominated by drought-resistant shrubs, small trees, and bushes, often with thick, waxy leaves to reduce water loss common species include manzanita, sagebrush, and various types of oaks

• Home to diverse wildlife, including mammals (e.g., coyotes, rabbits, and deer), reptiles (e.g., lizards, snakes), and numerous bird species (e.g., quails, hawks)

• Suffers through frequent fires

Desert

• Examples include the Sahara, Mojave, and Gobi

• Extreme temperatures (can exceed 50°C) with low rainfall

• Little to no vegetation, including succulents (e.g., cacti) and drought-resistant shrubs (e.g., sagebrush)

• Adapted organisms such as reptiles (e.g., lizards), small mammals (e.g., kangaroo rats), and specialized birds

• Incredibly dry

Tropical Savanna

• Found in Africa, South America, and Australia, typically between tropical rainforests and deserts

• Warm temperatures and seasonal rainfall with a distinct wet and dry season

• Dominated by grasses with scattered trees

• Large herbivores (e.g., elephants, giraffes), predators (e.g., lions, hyenas), and diverse avian species

• Fire-adapted ecosystems that rely on occasional wildfires to maintain the balance between grasslands and tree growth

Tropical Rainforest

• Near the equator in regions such as the Amazon basin, Congo Basin, and Southeast Asia

• Warm temperatures and high rainfall with high humidity

• Dense vegetation with towering trees, vines, ferns, and a rich variety of plant species

• High biodiversity, including countless insects, birds (e.g., parrots), mammals (e.g., monkeys), and reptiles (e.g., snakes)

• Nutrient-poor soils due to rapid decomposition and nutrient cycling; significant carbon storage and major role in global climate regulation

• Very productive species rich with nutrients tied to vegetation not soil

Populations

• Refer to groups of individuals of the same species living in a specific area

Community

• An assembly of different species interacting in a shared environment, influenced by factors like species diversity, population dynamics, and ecological relationships

Ecosystems

• Dynamic complexes of biological communities interacting with their physical environment, characterized by energy flow and nutrient cycling

• All of these share 2 essential features: Biotic (living organisms) and Abiotic (nonliving chemical) Environment

Biome

• A large ecological area characterized by specific climate conditions, trees, animals, and is classified based on shared environmental features

What is a niche?

• Refers to the role or function of an organism or species within an ecosystem, including its habitat, resource use, and interactions with other species

• It encompasses everything an organism does to survive—such as what it eats, how it interacts with other organisms, and how it contributes to the energy flow and nutrient cycling in its environment

• When 2 of this overlap 2 outcomes may happen: Competitive Exclusion (One species may utilize the resource more causing the other species to go extinct) or Resource Partitioning (The species alter their use of the niche dividing the resource)

Commensalism (+/o)

• Benefits one species and doesn’t affect the other

• ex: Bird making a nest on a tree

Mutualism (+/+)

• Benefits both species

• ex: Sea anemone and Anemone fish

Interspecific Competition

• Hurts both species

• ex: 2 animals fighting for the same food or mate

Predation (+/-)

• Helps one species at the expense of the other

• Usually kills its prey

• ex: An animal hunting and killing its prey

Parasitism (+/-)

• Lives on or in a host but doesn’t usually kill it

• Benefits from this relationship

• Ectoparasites = lives on host

• Endoparasites = lives in the host

• ex: Leeches leeching off animals

What are some adaptations to predation?

• Physical features like camouflage for hiding, speed for escaping, and defensive structures like spikes

• Behavioral adaptations may involve living in groups for protection or adopting strategies like playing dead to avoid being eaten

Keystone Species

• Species that have an unusually large influence on the presence or absence of numerous other species in the community

What limits the number of trophic levels?

• Limited by energy availability, as energy decreases at each level due to inefficiencies in energy transfer (remember only 10% of the energy gets transferred)

Biological magnification

• The process where toxic substances accumulate in higher concentrations at each trophic level of a food chain, impacting organisms more severely as they move up the chain

Primary Succession

• The ecological process that occurs in previously uninhabited environments where no soil exists, such as after a volcanic eruption or glacier retreat

• It begins with colonization by pioneer species, like lichens and mosses, which can survive in harsh conditions and contribute to soil formation

Secondary Succession

• Occurs in ecosystems that have been disturbed but still possess soil and some biological legacy (Primary succession with a head start)

• It follows events like wildfires or human activities, allowing for rapid recovery and re-establishment of vegetation due to remaining seeds and roots

• This process leads to a return to a stable community more quickly than primary succession

HIPPO

• Developed by E.O Wilson

• H = Habitat Loss

• I = Invasive Species

• P = Pollution

• P = Population (Human Overpopulation)

• O = Overharvesting (Poaching)

Endemic Species

• Species that are native and only found in one area

• ex: California Condor found solely in California

Endangered Species

• Species that is endangered of being extinct

Threatened Species

• Species at risk of extinction in the near future due to changes in their environment or population decline

Climate Change

• Long-term alteration of temperature and typical weather patterns in a region

• Primarily due to human activities such as burning fossil fuels, deforestation, and industrial processes, leading to increases in greenhouse gases like carbon dioxide and methane

• Results in severe weather events, rising sea levels, and disruption of ecosystems, impacting agriculture, biodiversity, and human health

Ozone Layer Issues

• When there is a hole in the Ozone layer an abundance of radiation comes in causing increased rates of cancer, and issues with the plants

Acid Rain

• Rain that is significantly more acidic than normal

• Caused by release of sulfur dioxides and nitrogen oxides into the air primarily from fossil fuels like coal and oil which react with water vapor, oxygen, and other chemicals in the atmosphere, forming sulfuric and nitric acids

• Can harm aquatic ecosystems, damage forests, and lead to the deterioration of buildings and monuments, particularly those made of limestone and marble

Hotspots

• Regions with significant biodiversity that are under threat from human activities, often identified as areas where conservation efforts are crucial due to the high number of endemic species and environmental pressures1

Know the different phyla of animals we covered and the sub groups. What are examples of each group?

What are characteristics of that group?(ex: phylum chordata- what are the 4 characteristics that they all have and a subcategory also known as a class would be sub phylum: vertebrates class: mammalia- all of them have hair and females have mammary glands

Phylum Chordata

• All members possess four key features at some stage: a notochord, a dorsal hollow nerve cord, pharyngeal slits, and a post-anal tail

• Subphylum Vertebrata includes classes such as Mammalia (e.g., humans, whales) which have hair and mammary glands for nursing their young

• ex: Humans, Whales, Seals

Phylum Arthropoda

• Segmented body with a distinct head, thorax, abdomen, and a exoskeleton made of chitin along with jointed appendages

• ex: Insects (e.g., ants, butterflies), arachnids (e.g., spiders, scorpions), and crustaceans (e.g., crabs, lobsters)

Phylum Mollusca

• Soft-bodied animals, many with a hard shell; they possess a mantle and a muscular foot

• ex: Snails and Clams

Phylum Annelida

• Segmented worms with a true coelom; they have a closed circulatory system and setae (bristle-like structures)

• ex: Earthworms and Leeches

Phylum Porifera

• Sponges (no tissue), body consist of a hollow tube with pores in its wall

• ex: Sponges

Phylum Cnidaria

• Radially symmetrical with tentacles armed w rows of stinging cells used to paralyze prey

• ex: Jellyfish

Phylum Enchinodermata

• Marine animals with radial symmetry, a calcareous endoskeleton, and a water vascular system for movement and feeding

• ex: Starfish, sea urchins, and sea cucumbers

Phylum Nematoda

• Unsegmented, cylindrical body; covered by a tough cuticle; bilateral symmetry; complete digestive system

• Roundworms, including parasitic species like hookworms and beneficial ones found in soil

Phylum Platyhelminthes

• Flat-bodied, soft-bodied animals with bilateral symmetry; lack a true coelom and possess a simple body structure

• ex: Flatworms, including planarians, flukes, and tapeworms

What is an Animal

• Animals are multicellular, eukaryotic organisms that are typically heterotrophic, meaning they consume other organisms for energy

• They are characterized by the absence of cell walls, the presence of nervous and muscular systems, and their ability to move voluntarily at some stage of their life cycle

Types of Symmetry

• Bilateral Symmetry (Humans)

• Radial Symmetry (Jellyfish)

• Asymmetry (Sponges)