Topic 2,3,4:Taxon systematics, Evolution Darwin, Evolution of a population Flashcards
What are the 7 characteristics of life
-order(cellular structures)
-regulation (regulation of metabolism, internal condition, temperature)
-energy processing/metabolism(process food, and reject waste)
-growth and development
-reproduce (make more individuals)
-respond to environment (they move away or defend against threat)
-evoltuioary adaptaton
is bacteria alive? are viruses alive? (using the 7 characteristics of life)
bacteria:
they reproduce, they have cellular structures, they can develop resistance to antibiotics
viruses: on its own it lacks the ability to achieve life.. so it isn’t
who developed the idea Scala naturae, and what is it?
Aristotle developed it
-Its the natural ladder, that was organized by complexity,humans are placed on the top since they are the most complex, superior beings
-species are fixed meaning that their have been perfectly created to match their environment
whats Taxonomy and its, and who created it
its the practice of naming and classifying organism, it was created by Carl Linnaeus
whats Nomenclature
a system of rules for naming things
whats systematics
the theory/ practice of classifying organisms based on evolutionary history (phylogeny)
whats phylogeny
it describes the evolutionary history of organisms that have evolved from a common ancestor
why are common names problematic
-their are different names for the same species
-same name for different species
-common names can also imply relationships that do not exist
ex.”northern waterthrush” isn’t a thrush but a warbler
what did Linnaean propose due to the confusion of using common names in science
-to use latin as universal language of scientific nomenclature (the rules for naming things)
-use unique binomen as name of each species
-classify and group species using a hierarchical category based on relatedness and or similarity (taxonomy)
who created the Binomial system of nomenclature
Carlos Linnaean
Whats the Linnaean system
-each species has a unique binomen
Binomial names have 2 parts:
1.genus name
2.specific name
both are italicized and genus is capitalized
together the genus and specific make the species name
the Linnaean system of classification (taxonomy levels)(classification)
(least related)Kingdom->Phylum->Class->Order->Family->genus->species (most related)
whats the name of the organisms in the nested subsets (taxonomic levels)
Taxa
Systematics- What are phylogenetic trees
they are evolutionary trees that show the evolutionary relationship between organisms (past and present):between common ancestors and their descendants
Phylogenetic trees are hypothesis for the evolutionary relationships
whats a taxon
named group at any level of classification
whats a clade
its a group that contains the all the descendants and its common ancestor
whats a polytomy
a word to describe a node that is linked to three or more descendants, this happens when the evolutionary relationship between the descendants is unresolved
what information is collected to construct phylogenetic trees
-Morphology (the argument/ structure of parts of an organism)
-Behaviour
-DNA sequences
-Biochemistry
whats phylogentics
its the study of the evolutionary relationship between taxa (species or individuals or genes)
what do branch points or nodes in phylogenetic trees symbolize
a common ancestor and a speciation event has occurred for the common ancestor to become 2 separate taxa
whats cladistics
its a method of biological classification which organism are categorized in groups based in shared derived characteristics from a common ancestor
sister taxa
are the most closely related
-they split from the same node
The In-group
the clade that is being studied
The Out-group
the one or more taxa that are distantly related to the in-group (clade being studied), they have diverged from the in-group at an earlier time
Character and state
the character is the type of structure, behaviour, DNA sequence
The state is the manifestation of that charter
ex. character : eye colour, state: orange
whats parsimony?
tells us that the most possible answer is the one that is simplest
Synapomorphy and Symplesiomorphy
when including the out-group and in-group the trait is synapomorphy (shared and derived)
but when only the in-group it is Symplesiomorphy (shared, ancestral state)
whats more useful for reconstructing phylogenetic trees (Synapomorphy or Symplesiomorphy)
synapomorphy
Homologous vs Analogous Characters
Homologous the same and have the same evolutionary origin (present in common ancestor of the taxa)
Analogous-appear the same but evolved separately (this is called covergent evolution)
covergent evolution
its the in-dependent evolution of similar features in different linages
Molecular phylogenetics
is the dominant form of identifying if taxa are related or not
-its the matching of bases in selected gene sequences
the more matches there are between species the more likely they are closely related
Monophyletic
(a trait present in this group is…)
contains the common ancestor and all its descendants (clade)
-traits present in monophyletic groups are HOMOLOGOUS TRAITS-since they are similar and have the same evolutionary origin