The non-living, physical aspects of this habitat, such as wave action and temperature, are known as ____________ factors. All the individuals of a single species of limpet, Patella vulgata, inhabiting this specific shoreline form a ____________. Together with the populations of seaweeds, barnacles, and predatory whelks living and interacting in the same area, they make up the ____________.

To quantify the distribution of these sessile or slow-moving species, ecologists use a square frame called a ____________. To ensure the sample is unbiased, the positions of these frames are selected using ____________ coordinates rather than subjective choice.

The sum of all individuals counted across all sample frames is divided by the total number of frames used to calculate the ____________ density. Carrying out a high number of replicate samples across the shore increases the ____________ of the estimated density and makes it easier to spot ____________ data points.