Topics 1 and 2: Biodiversity and Systematics Flashcards
Why is there an urgency to study biodiversity?
Human activities are threatening it, the loss of biodiversity has implications for humans.
What are some threats to biodiversity?
- resource exploitation
- conversion of land
- pollution
- transport of species
- global climate change
What are some direct benefits of studying biodiversity?
-can be useful in the production of drugs and can have agriculture value (source of food)
What are some indirect benefits of studying biodiversity?
- ecosystem services (biogeochemical cycles, nutrient cycling, H2O cycling, preventing soil erosion, regulating climate-carbon cycle)
- ecotourism
Population
a group of individuals of the same species
Community
several populations living together
Ecosystem
-is defined as a community+physical environment
What are the levels of biological organization?
- the biosphere
- ecosystems
- communities
- populations
- organisms
- organs and organ systems
- tissues
- cells
- organelles
- atoms and molecules
Theories
- Unifying explanations of the natural world
- have withstood rigorous scientific testing, challenging, and debate
- does NOT mean hypothesis
eg: cell theory, gene theory, theory of evolution
Laws
-is universally true and exception free (is very rare in biology)
Proximate Questions
-deal with the mechanism of things and do not always require evolutionary explanations
Ultimate Questions
-are concerned with the evolutionary origins and functions
Observation (discovery science)
-before we make a hypothesis, we first must observe things-making observations allows us to undergo hypothesis testing
Induction
- inference of a general law from specific observations
eg: all organisms are made of cells
Natural History
- patterns observed that are documented
- documentation of appearance, behavior, distribution, etc of organisms
What is a hypothesis?
- is a possible explanation for an observation
- knowledge-based
- testable and falsifiable (via observations and experiments)
Scientific Method
-evidence-based inquiry for understanding life
-hypothetico-deductive science
-uses deductive reasoning
“if…, then…” logic eg: if spiders who match backgrounds can catch more prey, they will survive and reproduce more”
-method is flexible
Deductive reasoning
-taking answers from a specific test and applying more generally
What are the characteristics of life?
- order (highly organized and composed of more than 1 cell)
- regulation and energy processing (metabolism)
- growth and development
- reproduction
- response to stimuli (environment)
- evolutionary adaptation
eg: seeds before germination are not living organisms, viruses are not living because need host
What are different ways in which we can catalog the diversity of life?
- Aristotle’s scala naturae
- Linnaeus
- Modern Systematics
How did the Scala Naturae organize species?
- species are fixed and unchanging
- they are created perfectly matched to their environment
- organized by complexity with man on top
What are some shortcomings with the scala naturae?
-if species are perfectly matched to their environment, how do they go extinct?
Nomenclature
a system of rules for naming things
Taxonomy
the practice of naming and classifying organisms
Systematics
the theory (and practice) of classifying organisms based on evolutionary history (phylogeny)