It makes sense that larger organisms have larger offspring, but what the mathematical form of this relationship should be is unclear. Let’s look at the problem empirically for mammals.
Download some
mammal life history data
from the web. You can do this either directly in the program using urllib or
download the file to your computer using your browser and import it from there.
Import the data into a Pandas data frame. There are some extra blank lines at
the end of this file, so get rid of them by using the optional read_csv()
argument, skip_footer=7.
Missing data in this file is specified by -999 and -999.00. Tell Pandas that
these are null values using the optional read_csv() argument,
na_values=['-999', '-999.00']. This will stop them from being plotted.
order is Rodentia, graph the log (base 10) of adult mass
vs. the log (base 10) of newborn mass. Label the axes.