Bio Lab Practical 1

survivorship rate

the fraction of individuals that survive selection over a given time frame calculated for each PHENOTYPE

survivorship rate equation

S = survivors / total

relative fitness equation

w = S / S_highest

S = survivorship rate for that phenotype

S_highest = highest survivorship rate among all phenotypes

selection coefficient (s)

the selection against a phenotype relative to the most successful phenotype

equation for selection coefficient (s)

s = 1 - w

excel command for counting number of values

=COUNT

excel command for adding values

=SUM

excel command for SD of a sample

=STDEV.S

Null hypothesis

reflects the case where nothing special or unexpected is happening / where one variable doesn’t affect the other

Alternative hypothesis

reflects the case where the null hypothesis is not true

What does a t-test do?

Assesses whether the means of two groups differ

using data analysis tools on excel, which T value do you use?

t Stat

using data analysis tools on excel, which P value do you use?

P(T<=t)two-tail

How do you add a y axis title?

Go to chart design, then add chart element

How do you scale the y-axis?

right click on the y-axis scaling, then input a min/max

systematics

the branch of biology that tries to uncover the evolutionary history (phylogeny) of groups of organisms

what does a node represent?

A common ancestor

what is a polytomy?

when a phylogeny is constructed with three or more taxa originating from the same node

clade

a group of organisms that includes a common ancestor and all the descendants of that ancestor

outgroup

a taxon that is closely related to a clade that is under study that helps to root the tree and determine whether a particular trait is likely ancestral in the clade

homoplasy

a trait shared between two groups due to convergent evolution

synapomorphy

a shared, evolutionarily derived trait that is present in two (or more) taxa and inherited from their most recent common ancestor

what is an SNP?

single nucleotide polymorphism — a mutation where just one nucleotide changes

what is the central dogma?

genetic info flows from template DNA strand, to mRNA, then to amino acids which make up proteins

silent mutation (synonymous mutation)

DNA change that doesn’t result in a change in the amino acid coded for by a codon

missense mutation

DNA change that does result in a different amino acid being placed in the protein

how do you conduct a t-test in excel?

go to data analysis, then click “t-test: two-sample assuming equal variances,” enter range by selecting cells, select random cell for output range, then enter