and Benchmarks: Biology Modules
The ETE biology related modules (Tropical Poison, Temperate
Rainforest, Rift Valley Fever, and Mountain Gorilla) support the following
science standards and benchmarks:
Science Education Standards (Science
Education Standards Online)
As a result of activities, students should develop understanding and abilities
aligned with the following concepts and processes.
Unifying Concepts & Processes (pp. 115-119)
concepts that underlie Systems, Order, and Organization include:
- A system is an
organized group of related objects or components that form a whole.
Systems can coexist, for example, of organisms, machines, fundamental
particles, galaxies, ideas, numbers, transportation, and education.
- Systems have boundaries,
components, resources flow (input and output), and feedback.
- Think and analyze
in terms of systems.
- The idea of simple
systems encompasses subsystems as well as identifying the structure
and function of systems, feedback and equilibrium, and the distinction
between open and closed systems.
- An understanding
of regularities in systems, and by extension, the universe; they then
can develop understanding of basic laws, theories, and models that explain
- An assumption
of order establishes the basis for cause-effect relationship and predictable.
- The behavior of
units of matter, objects, organisms, or events in the universe-can be
- Types of organization
provide useful ways of thinking about the world include the periodic
table of elements and the classification of living things
- Living systems
also have different levels of organization-for example, cells, tissues,
organs, organisms, populations, and communities.
that underlie Constancy, Change, and Measurement include:
- Interactions within
and among systems result in change.
- Changes vary in
rate, scale, and pattern, including trends and cycles.
- Energy can be
transferred and matter can be changed.
- Changes in systems
can be quantified.
- Evidence for interactions
and subsequent change and the formulation of scientific explanations
are often clarified through quantitative distinctions-measurement.
- Mathematics is
essential for accurately measuring change.
- Different systems
of measurement are used for different purposes.
- An important part
of measurement is knowing when to use which system.
- Scale includes
understanding that different characteristics, properties, or relationships
within a system might change as its dimensions are increased or decreased.
- Rate involves
comparing one measured quantity with another measured quantity.
that underlie Evidence, Models, and Explanation include:
- Evidence consists
of observations and data on which to base scientific explanations.
- Using evidence
to understand interactions allows individuals to predict changes in
natural and designed systems.
- Models are tentative
schemes or structures that correspond to real objects, events, or classes
of events, and that have explanatory power.
- Models help scientists
and engineers understand how things work.
- Models take many
forms, including physical objects, plans, mental constructs, mathematical
equations, and computer simulations.
- Scientific explanations
incorporate existing scientific knowledge and new evidence from observations,
experiments, or models into internally consistent, logical statements.
- Different terms,
such as "hypothesis," "model," "law,"
"principle," "theory," and "paradigm"
are used to describe various types of scientific explanations.
that underlie Evolution and Equilibrium include:
- Evolution is a
series of changes, some gradual and some sporadic, that accounts for
the present form and function of objects, organisms, and natural and
- The general idea
of evolution is that the present arises from materials and forms of
- Equilibrium is
a physical state in which forces and changes occur in opposite and off-setting
- Steady state,
balance, and homeostasis also describe equilibrium states. Interacting
units of matter tend toward equilibrium states in which the energy is
distributed as randomly and uniformly as possible.
A: Science as Inquiry (pp. 173-176)
abilities and concepts that underlie the Abilities Necessary
To Do Scientific Inquiry include:
- Identify questions
and concepts that guide scientific investigations.
- Use technology
and mathematics to improve investigations and communications.
- Formulate and
revise scientific explanations and models using logic and evidence.
- Recognize and
analyze alternative explanations and models
- Communicate and
defend a scientific argument.
that underlie the Understandings about Scientific Inquiry
- Scientists conduct
investigations for a wide variety of reasons:
- to discover
new aspects of the natural world,
- to explain
recently observed phenomena,
- to test the
conclusions of prior investigations or the predictions of current
- Scientists rely
on technology to enhance the gathering and manipulation of data.
- New techniques
and tools provide new evidence to guide inquiry and new methods to gather
data, thereby contributing to the advance of science.
- Mathematics is
essential in scientific inquiry. Mathematical tools and models guide
and improve the posing of questions, gathering data, constructing explanations
and communicating results.
- Scientific explanations
must adhere to criteria such as:
- a proposed
explanation must be logically consistent;
- it must abide
by the rules of evidence; it must be open to questions and possible
- and it must
be based on historical and current scientific knowledge.
- Results of scientific
inquiry-new knowledge and methods-emerge from different types of investigations
and public communication among scientists.
- In communicating
and defending the results of scientific inquiry, arguments must be logical
and demonstrate connections between natural phenomena, investigations,
and the historical body of scientific knowledge.
- The methods and
procedures that scientists used to obtain evidence must be clearly reported
to enhance opportunities for further investigation.
B: Physical Science (pp. 176-181)
concepts that underlie Conservation of Energy and the Increase in Disorder
- The total energy
of the universe is constant.
- Energy can be
transferred by collisions in chemical and nuclear reactions, by lightwaves
and other radiations, and in many other ways.
- Energy can never
be destroyed. As these transfers occur, the matter involved becomes
steadily less ordered.
- All energy can
be considered to be either kinetic energy, which is the energy of motion;
potential energy, which depends on relative position; or energy contained
by a field, such as electromagnetic waves.
- Everything tends
to become less organized and less orderly over time. Thus, in all energy
transfers, the overall effect is that the energy is spread out uniformly
when we burn fuels.
D: Earth & Space Science (pp. 187 & 190)
concepts that underlie Energy in the Earth System include:
- The sun is the
major external source of energy.
- Heating of earth's
surface and atmosphere by the sun drives convection within the atmosphere
and oceans, producing winds and ocean currents.
- Global climate
is determined by energy transfer from the sun at and near the earth's
surface. This energy transfer is influenced by dynamic processes such
as cloud cover and the earth's rotation, and static conditions such
as the position of mountain ranges and oceans.
C: Life Science (pp. 181 & 187)
concepts that underlie the Molecular Basis of Heredity include (Rift Valley
- In all organisms,
the instructions for specifying the characteristics of the organism
are carried in DNA, a large polymer formed from subunits of four kinds
(A, G, C, and T).
- The chemical and
structural properties of DNA explain how the genetic information that
underlies heredity is both encoded in genes (as a string of molecular
"letters") and replicated (by a templating mechanism). Each
DNA molecule in a cell forms a single chromosome.
- Transmission of
genetic information to offspring occurs through egg and sperm cells
that contain only one representative from each chromosome pair. An egg
and a sperm unite to form a new individual.
- Changes in DNA
(mutations) occur spontaneously at low rates. Some of these changes
make no difference to the organ ism, whereas others can change cells
and organisms. Only mutations in germ cells can create the variation
that changes an organism's offspring.
that underlie the Biological Evolution include:
- Species evolve
over time. Evolution is the consequence of the interactions of:
- the potential
for a species to increase its numbers,
- the genetic
variability of offspring due to mutation and recombination of genes,
- a finite supply
of the resources required for life, and
- the ensuing
selection by the environment of those offspring better able to survive
and leave offspring.
- Natural selection
and its evolutionary consequences provide a scientific explanation for
the fossil record of ancient life forms, as well as for the striking
molecular similarities observed among the diverse species of living
- The millions of
different species of plants, animals, and microorganisms that live on
earth today are related by descent from common ancestors.
that underlie the Matter, Energy, & Organization in Living Systems
- All matter tends
toward more disorganized states.
- Living systems
require a continuous input of energy to maintain their chemical and
physical organizations. With death, and the cessation of energy input,
living systems rapidly disintegrate.
- The energy for
life primarily derives from the sun. Plants capture energy by absorbing
light and using it to form strong (covalent) chemical bonds between
the atoms of carbon-containing (organic) molecules. These molecules
can be used to assemble larger molecules with biological activity (including
proteins, DNA, sugars, and fats).
- The complexity
and organization of organisms accommodates the need for obtaining, transforming,
transporting, releasing, and eliminating the matter and energy used
to sustain the organism.
- The distribution
and abundance of organisms and populations in ecosystems are limited
by the availability of matter and energy and the ability of the ecosystem
to recycle materials.
- As matter and
energy flows through different levels of organization of living systems-cells,
organs, organisms, communities-and between living systems and the physical
environment, chemical elements are recombined in different ways. Each
recombination results in storage and dissipation of energy into the
environment as heat. Matter and energy are conserved in each change.
that underlie the Interdependence of Organisms include:
- The atoms and
molecules on the earth cycle among the living and nonliving components
of the biosphere. (Tropical Poison, and Temperate Rainforest)
- Energy flows through
ecosystems in one direction, from photosynthetic organisms to herbivores
to carnivores and decomposers. (Tropical Poison, and Temperate Rainforest)
- Organisms both
cooperate and compete in ecosystems. The interrelationships and interdependencies
of these organisms may generate ecosystems that are stable for hundreds
or thousands of years.
- Living organisms
have the capacity to produce populations of infinite size, but environments
and resources are finite. This fundamental tension has profound effects
on the interactions between organisms.
- Human beings live
within the world's ecosystems. Increasingly, humans modify ecosystems
as a result of population growth, technology, and consumption.
- Human destruction
of habitats through direct harvesting, pollution, atmospheric changes,
and other factors is threatening current global stability, and if not
addressed, ecosystems will be irreversibly affected.
that underlie the Behavior of Organisms include:
- Organisms have
behavioral responses to internal changes and to external stimuli.
- Responses to external
stimuli can result from interactions with the organism's own species
and others, as well as environmental changes; these responses either
can be innate or learned.
- The broad patterns
of behavior exhibited by animals have evolved to ensure reproductive
success. Animals often live in unpredictable environments, and so their
behavior must be flexible enough to deal with uncertainty and change.
Plants also respond to stimuli.
- Like other aspects
of an organism's biology, behaviors have evolved through natural selection.
Behaviors often have an adaptive logic when viewed in terms of evolutionary
F: Science in Personal & Social Perspectives (pp. 193-199)
concepts that underlie Personal & Community Health include:
- The severity of
disease symptoms is dependent on many factors, such as human resistance
and the virulence of the disease-producing organism.
- Many diseases
can be prevented, controlled, or cured. Some diseases, such as cancer,
result from specific body dysfunctions and cannot be transmitted.
- Personal and social
factors- such as habits, family income, ethnic heritage, body size,
advertising, and peer pressure-influence nutritional choices.
that underlie Population Growth include:
- Populations grow
or decline through the combined effects of births and deaths, and through
emigration and immigration.
- Populations can
increase through linear or exponential growth, with effects on resource
use and environmental pollution.
- Various factors
influence birth rates and fertility rates, such as average levels of
affluence and education, importance of children in the labor force,
education and employment of women, infant mortality rates, costs of
raising children, availability and reliability of birth control methods,
and religious beliefs and cultural norms that influence personal decisions
about family size.
- Populations can
reach limits to growth. Carrying capacity is the maximum number of individuals
that can be supported in a given environment. The limitation is not
the availability of space, but the number of people in relation to resources
and the capacity of earth systems to support human beings.
- Changes in technology
can cause significant changes, either positive or negative, in carrying
that underlie Natural Resources include:
- Human populations
use resources in the environment in order to maintain and improve their
- Natural resources
have been and will continue to be used to maintain human populations.
- The earth does
not have infinite resources; increasing human consumption places severe
stress on the natural processes that renew some resources, and it depletes
those resources that cannot be renewed.
- Humans use many
natural systems as resources. Natural systems have the capacity to reuse
waste, but that capacity is limited. Natural systems can change to an
extent that exceeds the limits of organisms to adapt naturally or humans
to adapt technologically.
that underlie Environmental Quality include:
- Natural ecosystems
provide an array of basic processes that affect humans. Those processes
include maintenance of the quality of the atmosphere, generation of
soils, control of the hydrologic cycle, disposal of wastes, and recycling
- Humans are changing
many of these basic processes, and the changes may be detrimental to
- Materials from
human societies affect both physical and chemical cycles of the earth.
Many factors influence environmental quality.
- Factors that students
might investigate include population growth, resource use, population
distribution, over consumption, the capacity of technology to solve problems,
poverty, the role of economic, political, and religious views, and different
ways humans view the earth.
that underlie Natural & Human-Included Hazards include:
- Normal adjustments
of earth may be hazardous for humans.
- Humans live at
the interface between the atmosphere driven by solar energy and the
upper mantle where convection creates changes in the earth's solid crust.
- As societies have
grown, become stable, and come to value aspects of the environment,
vulnerability to natural processes of change has increased. Human activities
can enhance potential for hazards.
- Acquisition of
resources, urban growth, and waste disposal can accelerate rates of
- Some hazards,
such as earthquakes, volcanic eruptions, and severe weather, are rapid
- There are slow
and progressive changes that also result in problems for individuals
and societies. For example, change in stream channel position, erosion
of bridge foundations, sedimentation in lakes and harbors, coastal erosions,
and continuing erosion and wasting of soil and landscapes can all negatively
- Natural and human-induced
hazards present the need for humans to assess potential danger and risk.
- Many changes in
the environment designed by humans bring benefits to society, as well
as cause risks.
- Students should
understand the costs and trade-offs of various hazards-ranging from
those with minor risk to a few people to major catastrophes with major
risk to many people.
- The scale of events
and the accuracy with which scientists and engineers can (and cannot)
predict events are important considerations.
that underlie Science & Technology in Local, National, & Global
- Science and technology
are essential social enterprises, but alone they can only indicate what
can happen, not what should happen. The latter involves human decisions
about the use of knowledge.
basic concepts and principles of science and technology should precede
active debate about the economics, policies, politics, and ethics of
various science- and technology-related challenges. However, understanding
science alone will not resolve local, national, or global challenges.
- Progress in science
and technology can be affected by social issues and challenges. Funding
priorities for specific health problems serve as examples of ways that
social issues influence science and technology.
- Individuals and
society must decide on proposals involving new research and the introduction
of new technologies into society.
- Decisions involve
assessment of alternatives, risks, costs, and benefits and consideration
of who benefits and who suffers, who pays and gains, and what the risks
are and who bears them.
- Students should
understand the appropriateness and value of basic questions-"What
can happen?"- "What are the odds?"-and "How do scientists
and engineers know what will happen?"
- Humans have a
major effect on other species. For example, the influence of humans
on other organisms occurs through land use-which decreases space available
to other species-and pollution-which changes the chemical composition
of air, soil, and water.
E: Science & Technology (pp. 190-193)
concepts that underlie Abilities of Technological Design include:
- Identify a problem
or design an opportunity.
- Propose designs
choose between alternative solutions.
- Implement a proposed
- Evaluate the solution
and its consequences.
- Communicate the
problem, process, and solution.
that underlie Understandings About Science & Technology include:
- Scientists in
different disciplines ask different questions, use different methods
of investigation, and accept different types of evidence to support
their explanations. Many scientific investigations require the contributions
of individuals from different disciplines, including engineering.
- New disciplines
of science, such as geophysics and biochemistry often emerge at the
interface of two older disciplines.
- Science often
advances with the introduction of new technologies. Solving technological
problems often results in new scientific knowledge.
- New technologies
often extend the current levels of scientific understanding and introduce
new areas of research.
- Creativity, imagination,
and a good knowledge base are all required in the work of science and
- Science and technology
are pursued for different purposes. Scientific inquiry is driven by
the desire to understand the natural world, and technological design
is driven by the need to meet human needs and solve human problems.
- Technology, by
its nature, has a more direct effect on society than science because
its purpose is to solve human problems, help humans adapt, and fulfill
solutions may create new problems. Science, by its nature, answers questions
that may or may not directly influence humans. Sometimes scientific
advances challenge people's beliefs and practical explanations concerning
various aspects of the world.
G: History & Nature of Science (pp. 200-201)
concepts that underlie Science As a Human Endeavor include:
- Individuals and
teams have contributed and will continue to contribute to the scientific
- Pursuing science
as a career or as a hobby can be both fascinating and intellectually
- Scientists have
ethical traditions. Scientists value peer review, truthful reporting
about the methods and outcomes of investigations, and making public
the results of work. Violations of such norms do occur, but scientists
responsible for such violations are censured by their peers.
- Scientists are
influenced by societal, cultural, and personal beliefs and ways of viewing
the world. Science is not separate from society but rather science is
a part of society.
that underlie Nature of Scientific Knowledge include:
- Science distinguishes
itself from other ways of knowing and from other bodies of knowledge
through the use of empirical
- Standards, logical
arguments, and skepticism, as scientists strive for the best possible
explanations about the natural world.
- Scientific explanations
must meet certain criteria. First and foremost, they must be consistent
with experimental and observational evidence about nature, and must
make accurate predictions, when appropriate, about systems being studied.
- Scientific explanations
should also be logical, respect the rules of evidence, be open to criticism,
report methods and procedures, and make knowledge public.
- Explanations on
how the natural world changes based on myths, personal beliefs, religious
values, mystical inspiration, superstition, or authority may be personally
useful and socially relevant, but they are not scientific.
- Because all scientific
ideas depend on experimental and observational confirmation, all scientific
knowledge is, in principle, subject to change as new evidence becomes
- The core ideas
of science such as the conservation of energy or the laws of motion
have been subjected to a wide variety of confirmations and are therefore
unlikely to change in the areas in which they have been tested.
- In areas where
data or understanding are incomplete, such as the details of human evolution
or questions surrounding global warming, new data may well ead to changes
in current ideas or resolve current conflicts.
- In situations
where information is still fragmentary, it is normal for scientific
ideas to be incomplete, but this is also where the opportunity for making
advances may be greatest.
By the end of the 12th grade, students should know that:
Chapter 11, Common Themes
- A system usually
has some properties that are different from those of its parts, but
appear because of the interaction of those parts.
how things work and designing solutions to problems of almost any kind
can be facilitated by systems analysis.
- In defining a
system, it is important to specify its boundaries and subsystems, indicate
its relation to other systems, and identify what its input and its output
are expected to be.
- The successful
operation of a designed system usually involves feedback. The stability
of a system can be greater when it includes appropriate feedback mechanisms.
- Even in some very
simple systems, it may not always be possible to predict accurately
the result of changing some part or connection.
11C Constancy and
- A system in equilibrium
may return to the same state of equilibrium if the disturbances it experiences
- Large disturbances
may cause it to escape that equilibrium and eventually settle into some
other state of equilibrium.
- Things can change
in detail but remain the same in general (the players change, but the
team remains; cells are replaced, but the organism remains).
- Graphs and equations
are useful (and often equivalent) ways for depicting and analyzing patterns
- In many physical,
biological, and social systems, changes in one direction tend to produce
opposing (but somewhat delayed) influences, leading to repetitive cycles
- In evolutionary
change, the present arises from the materials and forms of the past,
more or less gradually, and in ways that can be explained.
- Most systems above
the molecular level involve so many parts and forces and are so sensitive
to tiny differences in conditions that their precise behavior is unpredictable,
even if all the rules for change are known.
- Predictable or
not, the precise future of a system is not completely determined by
its present state and circumstances but also depends on the fundamentally
uncertain outcomes of events on the atomic scale.
- Because different
properties are not affected to the same degree by changes in scale,
large changes in scale typically change the way that things work in
physical, biological, or social systems.
- As the number
of parts of a system grows in size, the number of possible internal
interactions increases much more rapidly, roughly with the square of
the number of parts.
Chapter 1, The Nature of Science
1A The Scientific
- Scientists assume
that the universe is a vast single system in which the basic rules are
the same everywhere.
- Change and continuity
are persistent features of science.
- In science, the
testing, revising, and occasional discarding of theories, new and old nearer
- Science is an
ongoing process leads to an increasingly better understanding of how
things work in the world but not to absolute truth.
1B Scientific Inquiry:
are conducted for different reasons, including to explore new phenomena,
to check on previous results, to test how well a theory predicts, and
to compare different theories.
- Hypotheses are
widely used in science for choosing what data to pay attention to and
what additional data to seek, and for guiding the interpretation of
the data (both new and previously available).
- Sometimes, scientists
can control conditions in order to obtain evidence. When that is not
possible for practical or ethical reasons, they try to observe as wide
a range of natural occurrences as possible to be able to discern patterns.
- There are different
traditions in science about what is investigated and how, but they all
have in common certain basic beliefs about the value of evidence, logic,
and good arguments. And there is agreement that progress in all fields
of science depends on intelligence, hard work, imagination, and even
- Scientists in
any one research group tend to see things alike, so even groups of scientists
may have trouble being entirely objective about their methods and findings.
For that reason, scientific teams are expected to seek out the possible
sources of bias in the design of their investigations and in their data
analysis. Checking each other's results and explanations helps, but
that is no guarantee against bias.
1C The Scientific
- Science disciplines
differ from one another in what is studied, techniques used, and outcomes
sought, but they share a common purpose and philosophy, and all are
part of the same scientific enterprise.
- Many problems
are studied by scientists using information and skills from many disciplines.
- Disciplines do
not have fixed boundaries, and it happens that new scientific disciplines
are being formed where existing ones meet and that some subdisciplines
spin off to become new disciplines in their own right.
- Scientists can
bring information, insights, and analytical skills to bear on matters
of public concern.
- Scientists as
a group can be expected to be no less biased than other groups are about
their perceived interests.
- The strongly held
traditions of science, including its commitment to peer review and publication,
serve to keep the vast majority of scientists well within the bounds
of ethical professional behavior. Deliberate deceit is rare and likely
to be exposed sooner or later by the scientific enterprise itself.
- Funding influences
the direction of science by virtue of the decisions that are made on
which research to support.
Chapter 4, The Physical Setting
that Shape the Earth:
- Plants alter the
earth's atmosphere by removing carbon dioxide, using the carbon to make
sugars and releasing oxygen. This process is responsible for the oxygen
content of the air.
- The formation,
weathering, sedimentation, and reformation of rock constitute a continuing
"rock cycle" in which the total amount of material stays the
same as its forms change.
- The slow movement
of material within the earth results from heat flowing out from the
deep interior and the action of gravitational forces on regions of different
4B The Earth:
- Life is adapted
to conditions on the earth, including the force of gravity that enables
the planet to retain an adequate atmosphere, and an intensity of radiation
from the sun that allows water to cycle between liquid and vapor.
- Weather (in the
short run) and climate (in the long run) involve the transfer of energy
in and out of the atmosphere.
- Solar radiation
heats the land masses, oceans, and air.
Chapter 5, The Living Environment
(Rift Valley Fever):
- Some new gene
combinations make little difference, some can produce organisms with
new and perhaps enhanced capabilities, and some can be deleterious.
- The sorting and
recombination of genes in sexual reproduction results in a great variety
of possible gene combinations from the offspring of any two parents.
- The information
passed from parents to offspring is coded in DNA molecules.
- Genes are segments
of DNA molecules. Inserting, deleting, or substituting DNA segments
can alter genes.
- An altered gene
may be passed on to every cell that develops from it. The resulting
features may help, harm, or have little or no effect on the offspring's
success in its environment.
- Gene mutations
can be caused by such things as radiation and chemicals.
- When mutations
occur in sex cells, the mutations can be passed on to offspring; if
they occur in other cells, they can be passed on to descendant cells
- The experiences
an organism has during its lifetime can affect its offspring only if
the genes in its own sex cells are changed by the experience.
- The many body
cells in an individual can be very different from one another, even
though they are all descended from a single cell and thus have essentially
identical genetic instructions.
5F Evolution of Life:
- The basic idea
of biological evolution is that the earth's present-day species developed
from earlier, distinctly different species.
- Natural selection
provides the following mechanism for evolution:
- Some variation
in heritable characteristics exists within every species, some of
these characteristics give individuals an advantage over others
in surviving and reproducing, and the advantaged offspring, in turn,
are more likely than others to survive and reproduce.
- The result
is the proportion of individuals that have advantageous characteristics
for survival and reproduction will increase.
- New heritable
characteristics can result from new combinations of existing genes or
from mutations of genes in reproductive cells. Changes in other cells
of an organism cannot be passed on to the next generation.
- Natural selection
leads to higher proportions of organisms in a population that are well
suited for survival in particular environments.
- Chance alone can
result in the persistence of some heritable characteristics having no
survival or reproductive advantage or disadvantage for the organism.
When an environment changes, the survival value of some inherited characteristics
- The theory of
natural selection provides a scientific explanation for the history
of life on earth as depicted in the fossil record and in the similarities
evident within the diversity of existing organisms.
- Evolution builds
on what already exists, so the more variety there is, the more there
can be in the future. But evolution does not necessitate long-term progress
in some set direction.
- Evolutionary changes
appear to be like the growth of a bush: Some branches survive from the
beginning with little or no change, many die out altogether, and others
branch repeatedly, sometimes giving rise to more complex organisms.
5A Diversity of Life:
- The variation
of organisms within a species increases the likelihood that at least
some members of the species will survive under changed environmental
conditions, and a great diversity of species increases the chance that
at least some living things will survive in the face of large changes
in the environment.
- The degree of
kinship between organisms or species can be estimated from the similarity
of their DNA sequences, which often closely matches their classification
based on anatomical similarities.
- Ecosystems can
be reasonably stable over hundreds or thousands of years. As any population
of organisms grows, it is held in check by one or more environmental
factors: depletion of food or nesting sites, increased loss to increased
numbers of predators, or parasites. If a disaster such as flood or fire
occurs, the damaged ecosystem is likely to recover in stages that eventually
result in a system similar to the original one.
- Like many complex
systems, ecosystems tend to have cyclic fluctuations around a state
of rough equilibrium. In the long run, however, ecosystems always change
when climate changes or when one or more new species appear as a result
of migration or local evolution.
- Human beings are
part of the earth's ecosystems.
- Human activities
can, deliberately or inadvertently, alter the equilibrium in ecosystems.
5E Flow of Matter
and Energy (Tropical Poison, and Temperate Rainforest):
- Layers of energy-rich
organic material have been gradually turned into great coal beds and
oil pools by the pressure of the overlying earth.
- By burning these
fossil fuels, people are passing most of the stored energy back into
the environment as heat and releasing large amounts of carbon dioxide.
- The amount of
life any environment can support is limited by the available energy,
water, oxygen, and minerals, and by the ability of ecosystems to recycle
the residue of dead organic materials.
- Human activities
and technology can change the flow and reduce the fertility of the land.
- The chemical elements
that make up the molecules of living things pass through food webs and
are combined and recombined in different ways.
- At each link in
a food web, some energy is stored in newly made structures but much
is dissipated into the environment as heat.
- Continual input
of energy from sunlight keeps the process (Flow of Matter and Energy)
Chapter 7, Human Society
Effects on Behavior:
- Cultural beliefs
strongly influence the values and behavior of the people who grow up
in the culture, often without their being fully aware of it. Response
to these influences varies among individuals.
- Social distinctions
are a part of every culture, but take many different forms, ranging
from rigid classes based solely on parentage to gradations based on
the acquisition of skill, wealth, or education.
- Heredity, culture,
and personal experience interact in shaping human behavior. Their relative
importance in most circumstances is not clear.
7C Social Change:
- The size and rate
of growth of the human population in any location is affected by economic,
political, religious, technological, and environmental factors. Some
of these factors, in turn, are influenced by the size and rate of growth
of the population.
- The decisions
of one generation both provide and limit the range of possibilities
open to the next generation.
- Mass media, migrations,
and conquest affect social change by exposing one culture to another.
- To various degrees,
governments try to bring about social change or to impede it through
policies, laws, incentives, or direct coercion. Sometimes such efforts
achieve their intended results and sometimes they do not.
7D Social Trade-offs:
- Benefits and costs
of proposed choices include consequences that are long-term as well
as short-term, and indirect as well as direct.
- The more remote
the consequences of a personal or social decision, the harder it usually
is to take them into account in considering alternatives.
- Benifits and costs
may be difficult to estimate.
- In deciding among
alternatives, a major question is who will receive the benefits and
who (not necessarily the same people) will bear the costs.
- Social trade-offs
are often generational:
- The cost of
benefits received by one generation may fall on subsequent generations.
- The cost of
a social trade-off is sometimes borne by one generation although
the benefits are enjoyed by their descendants.
7E Political and
- In the free-market
model, the control of production and consumption is mainly in private
hands. The best allocation of resources is believed to be achieved by
talent, and hard work are expected to be rewarded with success and wealth.
- Government's role
is primarily to protect political and economic freedoms for society
as a whole-even at the cost of some individual or group material benefits.
- In the central-planning
model, production and consumption are controlled by the government.
- The main purpose
of government is to promote comparable welfare for all individuals and
groups-even at the cost of some individual and group freedoms.
- In practice, countries
make compromises with regard to economic models. Central planning has
to allow for some individual initiative, and markets have to provide
some protection for unsuccessful competitors. The countries of the world
use elements of both systems and are neither purely free-market nor
entirely centrally controlled. Countries change, some adopting more
free-market policies and practices, others more central-planning ones,
and still others doing some of each.
7F Social Conflict:
- Conflict between
people or groups arises from competition over ideas, resources, power,
- Social change,
or the prospect of it, promotes conflict because social, economic, and
political changes usually benefit some groups more than others. That,
of course, is also true of the status quo.
- Conflicts are
especially difficult to resolve in situations in which there are few
choices and little room for compromise. Some informal ways of responding
to conflict-use of pamphlets, demonstrations, cartoons, etc.-may sometimes
reduce tensions and lead to compromise but at other times they may be
inflammatory and make agreement more difficult to reach.
- Conflict within
a group may be reduced by conflict between it and other groups.
- Intergroup conflict
does not necessarily end when one segment of society gets a decision
in its favor, for the "losers" may then work all the harder
to reverse, modify, or circumvent the change. Even when the majority
of the people in a society agree on a social decision, the minority
who disagree must be protected from oppression, just as the majority
may need protection against unfair retaliation from the minority.
7G Global Interdependence:
- The wealth of
a country depends partly on the effort and skills of its workers, its
natural resources, and the capital and technology available to it.
- The wealth of
a country also depends on the balance between how much its products
are sought by other nations and how much of other nations' products
- Even if a country
could produce everything it needs for itself, it would still benefit
from trade with other countries.
- Because of increasing
international trade, the domestic products of any country may be made
up in part by parts made in other countries.
- The international
trade picture is often complicated by political motivations taking priority
over economic ones.
- The growing interdependence
of world social, economic, and ecological systems does not always bring
greater worldwide stability and often increases the costs of conflict.
Chapter 8 ,The Designed World
- New varieties
of farm plants and animals have been engineered by manipulating their
genetic instructions to produce new characteristics.
- Government sometimes
intervenes in matching agricultural supply to demand in an attempt to
ensure a stable, high-quality, and inexpensive food supply.
- Regulations are
often also designed to protect farmers from abrupt changes in farming
conditions and from competition by farmers in other countries.
- Agricultural technology
requires trade-offs between increased production and environmental harm
and between efficient production and social values. In the past century,
agricultural technology led to a huge shift of population from farms
to cities and a great change in how people live and work.
8F Health Technology
(Rift Valley Fever):
- Owing to the large
amount of information that computers can process, they are playing an
increasingly larger role in medicine to analyze data and to keep track
of diagnostic information about individuals and statistical information
on the distribution and spread of various maladies in populations.
- Almost all body
substances and functions have daily or longer cycles. These cycles often
need to be taken into account in interpreting normal ranges for body
measurements, detecting disease, and planning treatment of illness.
- Knowledge of genetics
is opening whole new fields of health care:
- In treatment,
substances from genetically engineered organisms may reduce the
cost and side effects of replacing missing body chemicals.
use weakened germs (or parts of them) to stimulate the
- The body's immune
system to react. This reaction prepares the body to fight subsequent
invasions by actual germs of that type.
- Some inoculations
last for life.
- The diagnosis
and treatment of mental disorders are improving but not as rapidly as
for physical health.
has contributed to health improvement in many ways, but its cost and
application have led to a variety of controversial social and ethical
Chapter 12, Habitats of Mind
Values and Attitudes:
- Know why curiosity,
honesty, openness, and skepticism are so highly regarded in science
and how they are incorporated into the way science is carried out; exhibit
those traits in their own lives and value them in others.
- View science and
technology thoughtfully, being neither categorically antagonistic nor
12B Computation and
Estimation in appropriate problems:
- Find answers to
problems by substituting numerical values in simple algebraic formulas
and judge whether the answer is reasonable by reviewing the process
and checking against typical values.
- Make up and write
out simple algorithms for solving problems that take several steps.
- Use computer spreadsheet,
graphing, and database programs to assist in quantitative analysis.
- Compare data for
two groups by representing their averages and spreads graphically.
- Express and compare
very small and very large numbers using powers-of-ten notation.
- Trace the source
of any large disparity between an estimate and the calculated answer.
- Consider the possible
effects of measurement errors on calculations.
- Learn quickly
the proper use of new instruments by following instructions in manuals
or by taking instructions from an experienced user.
- Use computers
for producing tables and graphs and for making spreadsheet calculations.
- Make and interpret
- Write clear, step-by-step
instructions for conducting investigations, operating something, or
following a procedure.
- Choose appropriate
summary statistics to describe group differences, always indicating
the spread of the data as well as the data's central tendencies.
- Describe spatial
relationships in geometric terms such as perpendicular, parallel, tangent,
similar, congruent, and symmetrical.
- Use and correctly
interpret relational terms such as if . . . then . . . , and, or, sufficient,
necessary, some, every, not, correlates with, and causes.
- Participate in
group discussions on scientific topics by restating or summarizing accurately
what others have said, asking for clarification or elaboration, and
expressing alternative positions.
- Use tables, charts,
and graphs in making arguments and claims in oral and written presentations.
- Notice and criticize
arguments based on the faulty, incomplete, or misleading use of numbers,
such as in instances when:
- Average results
are reported, but not the amount of variation around the average
- Check graphs
to see that they do not misrepresent results by using inappropriate
scales or by failing to specify the axes clearly.
- Wonder how
likely it is that some event of interest might have occurred just
- Insist that
the critical assumptions behind any line of reasoning be made explicit
so that the validity of the position being taken-whether one's own
or that of others-can be judged.
- Be aware,
when considering claims, that when people try to prove a point,
they may select only the data that support it and ignore any that
would contradict it.
- Suggest alternative
ways of explaining data and criticize arguments in which data, explanations,
or conclusions are represented as the only ones worth consideration,
with no mention of other possibilities. Similarly, suggest alternative
trade-offs in decisions and designs and criticize those in which major
trade-offs are not acknowledged