Chapter 15 - Orgins Of Biological Diversity Flashcards
Speciation?
the origin of new species
Biological Species Concept?
defines a species as a population or group of populations whose members have the ability to breed with one another in nature and produce fertile offspring
Macroevolution?
major evolutionary changes
(ex : speciation or extinction)
(Darwin thought was a gradual process)
Reproductive Isolation?
the inability of different species to interbreed
ex : different mating sequences, behaviors of attracting mates
Geographic Isolation?
an event that can lead to speciation that occurs when a population becomes separated from the rest of the species due to geographic change or movement to an isolated place.
______ occurs if the adaptations lead to _______.
Speciation ;
Reproductive Isolation
Adaptive Radiation?
process when populations of a species evolve adaptations to a variety of environments to form diverse, new species.
Punctuated Equilibrium?
evolution occurs with long periods of little change with shorter periods of rapid change.
Embryology?
the study of how organisms develop from fertilized eggs to fully formed organisms.
A fossils ______ in layers of sedimentary rock reveals it’s ____ compared to other fossils. This shows the fossil’s ______ age.
placement ;
age;
relative
Radiometric Dating?
method used to determine absolute age based on the amount of radioactive isotopes in a fossil.
What do scientists use to calculate absolute age?
the fossils half life, which is the time it takes for 50% of the original sample to decay.
The Geologic Time Scale? Name the 4 Eras?
organizes Earth's history into 4 eras : Precambrian Paleozoic Mesozoic Cenozoic
The boundaries between Earth’s eras are marked in the fossil record by __________.
major changes in life forms
can be explained by continental drift
Continental Drift?
the movement of Earth’s continents on large plates of crust
ex : “supercontinent” formed called Pangaea
Mass extinction?
great species loss
gives surviving organisms new opportunities & leads to adaptive radiation
Taxonomy? What are the two goals of taxonomy?
branch of biology that involves the identification, naming and classifying species
goals :
1- to assign a universal, scientific name to every species
2- to organize the diversity of life by classifying species into larger groups of related species
Binomial?
two part name for a species
genus and species
Phylogenetic Tree?
diagram that shows hypothesized evolutionary relationships
Convergent Evolution?
a process in which unrelated species from similar environments have adaptations that are very similar
Analogous Structures?
similar adaptations of convergent evolution
Cladistics?
a way to classify based on derived characters (homologous structures that occur in a clade in a phylogenic tree)
Derived Characters?
homologous structures that do not occur outside a particular branch (or clade)
Cladograms?
phylogenetic trees that specify the derived characters of clades to show relationships
3 Domain System?
Bacteria, Archaea, (both prokaryotes) and Eukaryotes.
5 Kingdom System? Proposed by ________.
Monerans, Protists, Plants, Fungi and Animals ;
Whittaker
