Ecology

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Ecology
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Ecology
Ecology is the study of interactions among
organisms and their environment.
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Ecologists are scientists who study these
relationships. Ecologists divide the
environmental factors that influence organisms
into two groups (abiotic and biotic factors).
Many times, ecologists must travel to specific
environments to examine the organisms that live
there.
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Food Chain, Webs, and Pyramid
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ENERGY FLOW AMONG ORGANISMS

• Everything you do requires energy. How do you
  get the energy that you need?

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• All living things get energy from their food to
  carry out life processes.

Plants make their food.
Animals eat their food.
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• A food chain shows how each living thing gets its
  food. Plants make food using energy from the
  sun. Some animals eat plants and some animals
  eat other animals. Each link in a chain is food
  for the next link. Arrows indicate the direction
  of energy flow.

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FOOD CHAIN
A food chain is the passing of food energy from
one organism to another.
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Plants are called producers because they are able
to use the energy from the sun to produce the
food they need using carbon dioxide and water.
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Animals cannot make their own food so they must
eat plants and/or other animals. They are called
consumers. There are three groups of consumers.
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A herbivore is called a primary, or first order
consumer because it eats the producers. A
carnivore that eats herbivores is a secondary, or
second order consumer. Some predators are called
tertiary, or third order consumers. These
animals usually have no predators.
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Some animals eat dead animals or carrion. They
are called scavengers. They help break down or
reduce organic material into smaller pieces.
roach
vulture
hyeina
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DECOMPOSERSOrganisms (bacteria and fungi) which
feed on decaying matter.

• Decomposers and scavengers break down dead plants
  and animals. They also break down the waste
  (feces) of other organisms. Decomposers are very
  important for any ecosystem. If they weren't in
  the ecosystem, the plants would not get essential
  nutrients, and dead matter and waste would pile
  up.

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FOOD WEBS

• Most organisms are part of more than one food
  chain. Many animals eat more than one kind of
  food in order to meet their food and energy
  requirements. These interconnected food chains
  form a food web.

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Food Web
All energy comes from the sun - which makes it
the top of the food chain.
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MARINE FOOD WEB
http//www.gould.edu.au/foodwebs/kids_web.htm
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ENERGY PYRAMID
Because a large amount of energy is lost at each
link, the further along the food chain you go,
the less energy is available. We use the energy
pyramid as a model to show decreasing available
energy at each level in the pyramid.
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0.1 energy
1 energy
10 energy
100 energy
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Why are there more primary consumers than
secondary?

• In a food chain, energy is passed from one link
  to the next.
• Organisms along a food chain pass on much less
  energy in the form of biomass (total amount of
  matter used as energy) than they receive.

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Plant and animal interactions
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Producer/Consumer
Living things that eat the remains and waste of
plants and animals. Like bacteria, It breaks
down organic material.
A living thing that makes food using materials
from the environment (nutrients) the Sun.
Primary - uses food produced by plants (eats
plants) Secondary - obtains energy by eating
primary consumer (eats meat)
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Producers vs. Consumers

• Producers are plants
• Grass
• Trees
• Flowers
• Weeds
• The produce energy through photosynthesis

• Consumers are animals (including humans)
• Bacteria (also decomposer)
• insects
• rodents
• dog/wolf/fox
• bears

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INTERACTIONS AMONG ORGANISMS

• Predator-prey
• An animal that hunts or kills other animals for
  food is called a predator.
• An animal that is eaten by another is called
  prey.

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Can you match some predator-prey relationships?
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Predator Prey
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Symbiosis

• Symbiosis is a long term relationship between 2
  or more species
• - Mutualism both organisms benefit
• ex. Coral (home) and algae (food)
• - Commensalism One organism is helped, while
  the other is neither helped or harmed
• ex. Remoras ride on sharks and eat what they
  leave behind in food scraps
• - Parasitism one benefits (parasite) the other
  is harmed (host) and weakened
• ex. ticks

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All organisms of the same species that live in
the same place.
A living thing
Population that shares an area
All populations within a certain area.
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Biome - a large geographical area having the
same climate and major life forms.
A ecosystem is a group of organisms their
physical environment.
In an ecosystem you have three classes of
consumers Herbivore - eats plants only Carnivore
- eats meat Omnivore - eats both
A habitat is where an organism lives within an
ecosystem.
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Ecosystems
An ecosystem is the biotic community and its
abiotic factors. Examples of ecosystems include
coral reefs, forests, and ponds.
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Biodiversitythe differences in living things in
an ecosystem

• The total number of species and biological
  communities in a region and the amount of genetic
  variation in each species
• The loss of biodiversity is a huge ecological
  problem
• Genetic diversity decreases as its populations
  decline- consequences in a population to adapt to
  changing environment
• Genetic variability-measure of its potential to
  adapt evolutionary insurance policy

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_______ _______
The carrying capacity is the maximum population
size that can live in an environment over time.
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Limiting Factor

• A limiting factor is a biotic or abiotic factor
  that restricts the size of a population.
• Food can be a limiting factor if the amount of
  food can only support a certain number of an
  animal in a population.

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Limiting factors

• Biotic factors are the living or once-living
  parts of the environment (plants, animals-prey,
  etc)
• Abiotic factors are the nonliving parts of the
  environment (light, water, air, nutrients, soil,
  minerals, nesting sites)

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Competition

• The interaction between two or more organisms, or
  groups of organisms, that compete for the same
  resources (in short supply)
• Can be between members of the same species and/or
  members of the different species
• Most important aspects of natural selection
• Results
• reduction in the numbers of one or both
  competitors-
• Distribution of organisms in habitats

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Ensuring Biodiversity

• Limit pollution (air, soil, water)
• Control transport of invasive species
• Limit the use of natural resources (clear cutting
  rainforests, interfering with river flow to
  wetlands, slow down oil and gas consumption)
• Conserve natural resources
• Protect endangered species (plants and animals)

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Ecological Succession- the orderly changes in a
ecosystem as one type of community changes into
another

• Pioneer species lichens and mosses live in
  area and grow on rocks, releasing acids that
  break them down over time to form soil
• Plants start to grow in soil
• Small animals move into area
• Large animals feed on smaller animals
• Organisms die leaving richer soil supported
  larger plants shrubs
• Soil becomes richer supporting trees
• Reaches a stable point of established growth know
  as a climax community