Lab 1 Flashcards
the process through which certain inherited traits become more or less common in a population because these traits are associated with reproductive success (or …) is called …
fitness; natural selection
to measure variation, we have to identify …, or … which we can evaluate in some quantitative way
discrete properties; traits
analyzing variation entails … variation as the starting point, with the second step being to identify the … we see in nature
measuring; source of variation
much biological variation, especially among individuals of the same species, is … in origin
environmental
the second main source of variation is … in origin
genetic
genetic differences are … and are therefore subject to …
heritable; natural selection
genetic variation may exist for a trait that is also influenced by environmental factors. we then say that the trait exhibits a … x … interaction
genotype; environment
some traits are quantified by counting them. the entity is either present/not present. these are … traits
discrete
other traits are measured on a … scale. values for the trait in this case can take fractional measurements
continuous
commonalities btwn discrete and continuous traits:
- they can take a wide variety of values
- a value of zero means something real
- there is a … in values
ranking
… variables are variables that are ranked, but not measured in a precise way
ordinal
… or … variables include things like sex, color, presence/absence of wings etc. for such variables, we cannot compute an average. . the same is true of ordinal variables
categorical; nominal
limits on size and shape affecting the performance of a biological trait are called … and they help to explain why many species’ characteristics remain within predictable ranges
functional constraints
we use a … of individuals to represent the whole
sample
researchers try to avoid …, or sampling flaws that overrepresent individuals of one type and under represent others
bias
mu is used for the …
unknown mean
models and tests based on a normal curve are called … statistics
parametric
… tests are developed for non-standard curves
non-parametric
the sample size must be large enough to eliminate … due to chance departures from the population mean
sampling errors
to measure the amount of variation around the mean we use a statistic called the …
standard deviation
the … is the square of the standard deviation
variance
a difference is considered … when it is found to be unlikely to be due to chance
statistically significant
the … is a default explanation which states that nothing interesting has been observed, that there is no relationship between two variables, or that there is no diference between groups
null hypothesis
if the test provides a probability or p-value equal or less than …, we reject the null hypothesis and accept an alternative hypothesis
0.05
the … test is used to determine whether there is a significant difference in the mean value of some variable between two different groups the null hypothesis of one of these tests is that there is no difference in the variable between the groups
t
