Do Humans (Homo sapiens) Maximize the Number of Food Items Per Foraging Run? A Test of the Marginal Value Theorem

804 Words 4 Pages
Abstract

Organisms such as starlings and honeybees appear to forage based on the marginal value theorem. This experiment tested whether humans could forage in like manner. An equal number of students took long and short routes to the foraging patch and collected simulated food items in a way that simulated diminishing marginal returns. Data on travel time, foraging time, and number of food items collected were collected. The data differed significantly from the calculated optimal values. This may be a result of low number of trips between the foraging patch and the simulated dwelling.

Introduction

When animals forage, many factors become involved. They include the location of the food, its distance from the animals’ dwelling,
…show more content…
Methods

A group of 14 students, aged 19-22 years, was divided into 7 groups of 2. Each member of every group was assigned either a long or short route to the simulated foraging patch, Room XXX. Students using the short route walked directly from the dwelling to the foraging patch, while students using the long route walked down a hallway, up a staircase, across the building, down a staircase, then into the foraging patch. Each run consisted of a group member leaving the dwelling, which contained a plastic cup representing offspring, entering the foraging patch, and returning. In the foraging patch, two trays of M & Ms were present. Students picked up one M & M from each tray during the first lap. On the second lap, students skipped one tray and picked up one M & M from the second. The pattern of skipping one more tray with each lap simulated diminishing marginal returns. Between 8 and 10 runs were conducted per route. Time spent travelling between the dwelling and foraging patch, foraging time, and number of M & Ms were recorded. Collected data was then compared to the optimal number of M & Ms for each route and analyzed using a Wilcoxon signed-rank rest. The optimal number of M & Ms was obtained using Fig. 2. Results were then compared to the results of similar experiment conducted in 1999. Fig. 2. A graph of the marginal value theorem using data from a set of 8 long route

Related Documents