The Fossil Record and Chapters 17 & 18 Flashcards
What is one of the things that helps provide evidence about the history of life on earth? What does that history include?
The fossil records provides evidence about the history of life on Earth and shows how different groups of organisms, including species, have changed over time.
What is the fun fact thing?
99% of all species that have ever lived on Earth have become extinct
Where do most fossils form?
In sedimentary rock
What usually forms in sedimentary rock?
Fossils
Define paleontologists
Scientists who study fossils
What is created when exposure to the elements breaks down existing rock into small particles of sand, silt, and clay?
Sedimentary rock
What is it called when the age of a fossil is determined by its placement with that of fossils in other layers of rock
Relative dating
What do scientists use to compare the relative age of fossils?
Index fossils
What is a species that is recognizable and existed for a short period but had a wide geographic range?
An index fossil
What are some characteristics of an index fossil?
It’s recognizable and existed for a short period but had a wide geographic range
What do you use to determine the age of a sample based on the amount of remaining radioactive isotopes it contains
Half-lives
What is the length of time required for half of the radioactive atoms in a sample to decay?
Half-life
What was developed through fossils (animals and plants) in layers of rock and by using radioactive dating?
The Geologic Time Scale
How was the Geologic Time Scale developed?
It was developed through fossils (animals and plants) in layers of rock and by using radioactive dating
What is the oldest period of time?
Precambrian time
What is the period inside the Precambrian era?
The Vendian era
What are the 3 eras?
Paleozoic, Mesozoic, and Cenozoic
What era covers 88% of history?
Precambrian time
How much time does the Precambrian Era cover?
About 88% of Earth’s history
What is the order of the time periods from oldest to newest?
Vendian, Cambrian, Ordovician, Silurian, Devonian, Carboniferous, Permian, Triassic, Jurassic, Cretaceous, Tertiary, and Quaternary
What’s the order from oldest to newest time periods in the paleozoic era?
Cambrian, Ordovician, Silurian, Devonian, Carboniferous, and Permian
What’s the order from oldest to newest time periods in the mesozoic era?
Triassic, Jurassic, Cretaceous
What’s the order from oldest to newest time periods in the cenozoic era?
Tertiary, Quaternary
What term is used to refer to large-scale evolutionary patterns and processes that occur over long periods of time?
Macroevolution
What is macroevolution?
Biologists use the term to refer to large-scale evolutionary patterns and processes that occur over long periods of time
What are the 6 important topics of macroevolution?
Extinction, Adaptive radiation, convergent evolution, coevolution, punctuated equilibrium, and changes in developmental genes
What do extinction, adaptive radiation, convergent evolution, coevolution, punctuated equilibrium, and changes in developmental genes all have in common?
They’re all topics of macroevolution
What resulted in a burst of evolution that produced new species?
[mass] extinctions
What resulted in open habitats and provided ecological opportunities for those organisms that survived?
Extinction
What happens when a single species or small group of species evolves through natural selection and other processes into diverse forms that live in different ways?
Adaptive Radiation
What is adaptive radiation?
When a single species or small group of species evolves through natural selection and other processes into diverse forms that live in different ways
What is it called when unrelated organisms come to resemble one another and natural selection molds different body structures like legs and arms into modified forms like wings or flippers?
Convergent evolution
What is convergent evolution?
When unrelated organisms come to resemble one another and natural selection molds different body structures like legs and arms into modified forms like wings or flippers
What is it called when organisms that are closely connected to one another by ecological interactions evolve together, evolutionary changes in one organism may be followed by a corresponding change in another organism, and two species evolve in response to changes in each other over time?
Coevolution
What is coevolution?
When organisms that are closely connected to one another by ecological interactions evolve together, evolutionary changes in one organism [may] be followed by a corresponding change in another organism, and two species evolve in response to changes in each other over time.
What is a pattern of long, stable periods interrupted by brief periods of more rapid change called?
Punctuated equilibrium
What is punctuated equilibrium?
A pattern of long, stable periods interrupted by brief periods of more rapid change called?
What might explain how differences evolve?
Changes in the expression of developmental genes [“body plans”]
What is the balanced distribution of duplicate body parts or shapes?
Symmetry in biology
What are the 3 types of symmetry?
Radial symmetry, bilateral symmetry, and spherical symmetry
Do most organisms exhibit symmetry or not?
Most organisms exhibit some sort of symmetry, a small minority are asymmetric
What is approximate in nature and biology?
Symmetry
What’s one example of approximate symmetry?
Plant leaves- they’re considered symmetric but rarely match up perfectly when folded in half
What means being capable of being split int o two equal parts so that one part is a mirror image of the other?
Bilateral symmetry
What is bilateral symmetry?
Being capable of being split int o two equal parts so that one part is a mirror image of the other
What is it called when organisms resemble a pie where several cutting planes produce roughly identical pieces?
Radial symmetry
What kind of organisms exhibit no left or right sides and only has top and bottom surfaces?
An organism with radial symmetry
What is spherical symmetry?
When an animal is a sphere (like a sea urchin)
What kind of symmetry do starfish exhibit as adults?
Pentaradial symmetry
What kind of symmetry are starfish’s ancestors believed to have had?
Bilateral symmetry
What kind of organisms exhibit bilateral symmetry only as larval forms?
Starfish, as well as other echinoderms, exhibit bilateral symmetry only as larval forms
What is a key theme in ecology?
Interdependence
What do species interact with?
Both other species and their nonliving environment
What is it called when one change can affect all species in an ecosystem?
Interdependence
What is interdependence?
One change can affect species in an ecosystem
What is the hierarchy of organization in the environment?
Biosphere, ecosystem, community, population, and organism
What is the broadest, most inclusive level of organization is the biosphere, the volume of Earth and its atmosphere that supports life?
The biosphere
What includes all of the organisms and the nonliving environment found in a particular place?
An ecosystem
What is all the interacting organisms living in an area?
A community
What is the level of organization where the focus is on the individual organisms of a single specis?
The population
What are biotic and abiotic factors?
Biotic factors are living factors. Abiotic factors are nonliving factors that influence organisms (climate, sunlight, pH, etc)
What is it called when some organisms can adjust their tolerance to abiotic factors?
Acclimation
What is an organism called when it can’t regulate their internal condition and they change as their external environment changes?
A conformer
What kind of organisms use energy to control some of their internal conditions?
Regulators
How do some species survive unfavorable conditions?
By becoming dormant or by migrating
What is a way of life, or role, in an ecosystem?
A niche
Most of what are photosynthetic and make carbohydrates by using energy from the sun?
Producers
What is the rate at which producers in an ecosystem capture the energy of sunlight by producing organic compounds?
Gross primary productivity
What is the rate at which biomass accumulates called?
Net primary productivity
What obtains energy by eating other organisms and includes herbivores, omnivores, carnivores, detritivores, and decomposers?
Consumers
What is a single pathway of energy transfer called?
A food chain
What is a network showing all paths of energy transfer called?
A food web
Why do ecosystems contain only a few trophic levels?
Because there is a low rate of energy transfer between each level
What contains only a few trophic levels because there is a low rate of energy transfer between each level?
Ecosystems
What are the key processes in the water syscle?
Evaporation, transpiration, and precipitation
Photosynthesis and cellular respiration are the two main steps in what?
The carbon cycle
Nitrogen-fixing bacteria are important in what because they change nitrogen gas into a usable form of nitrogen for plants?
The nitrogen cycle
What is the mort important thing in the nitrogen cycle?
Nitrogen-fixing bacteria
What happens in the phosphorous cycle?
Phosphorus moves from the phosphate deposited in rock, to the soil to living organisms, and finally to the ocean
What is the variety of organisms considered at all levels from populations to ecosystems?
Biodiversity
Who replaced Aristotle’s classification system and why?
Naturalists replaced Aristotle’s classification system because it did not adequately cover all organisms and because his use of common names was problematic
What is the science of describing, naming, and classifying organisms?
Taxonomy
What did Carolus Linnaeus devise?
He created a seven-level hierarchical system for classifying organisms according to their form and structure
What are the origional seven levels of the Linnaean system?
Kingdom, phylum, class, order, family, genus, and species
What is binomial nomenclature?
Assigning each species a two-part scientific name- a genus name and a species identifier
What is the system of assigning each species a two part name called?
Binomial nomenclature
What analyzes the diversity of organisms in the context of their natural relationships?
Systematics
What do scientists consider when classifying organisms?
Fossils, homologous features, embryos, chromosomes, and the sequences of proteins and DNA
What displays how closely related a subset of taxa are thought to be?
A phylogenetic diagram
What provides evidence of shared ancestry?
Homologous features as well as similarities in patterns of embryological development provides information about common ancestry
What uses shared derived characters as the only criterion for grouping taxa?
Cladistics
What is molecular cladistics?
Molecular similarities such as similar amino acid or nucleotide sequences, as well as chromosome comparisons, can help determine common ancestry
What is cladistics?
Finding common ancestry
Analyzing karyotypes can provide more information on what?
Evolutionary relationships
What can cladistics be mapped on?
A cladogram
What led to a new tree of life?
The phylogenetic analysis of rRNA nucleotide sequences by Carol Woese
What does the new “tree of life” consist of?
Three domains aligned with six kingdoms
What are the three domains?
Archaea, bacteria, and Eukarya
What does domain bacteria align with and what does it consist of?
Domain bacteria aligns with kingdom eubacteria, which consists of single-celled prokaryotes that are true bacteria
What does domain Archaea align with and what does it consist of?
Domain Archaea aligns with Kingdom Archaebacteria, which consists of single-celled prokaryotes that have distinctive cell membranes and cell walls
What 4 Kingdoms does Domain Eukarya align with and what does it consist of?
It includes the Kingdoms Protista, Plantae, Fungi, and Animalia. All members of Domain Eukarya have eukaryotic cells
