Biology Lab Report

Determining the habitat preference of Artemia franciscana by creating artificial gradients of three abiotic factors: light, pH, and temperature

Introduction

In the study of ecology, species are often described as generalists if they live in broad environmental conditions or specialists if they live in narrow or specific environmental conditions (Reece et al. 2011). Artemia franciscana, the organism under study, is a well known generalist that has adapted it's reproductive strategy to allow populations to withstand harsh environmental conditions (Gajardol et al. 2001). More specifically, A. franciscana are known to live in high salinity lakes that are often basic (Biology 108 Lab Manual 2015). Furthermore, A. franciscana feed on photosynthetic phytoplankton which inhabit areas of light availability but are also more susceptible to predation in highly-lit areas (Biology 108 Lab Manual 2015). Also, A. franciscana can withstand a broad range of temperature except extreme values may affect survival (Biology 108 Lab Manual 2015).

In this experiment, the habitat
franciscana distribution frequency were significant (X2calc = 49.4, X2crit = 7.81, df = 3, p < 0.05). This was also the case for the pH treatment (X2calc = 104.2, X2crit = 7.81, df = 3, p < 0.05). The result of the light treatment is supported by the Biology 108 Lab Manual (2015) which states that A. franciscana feed on photosynthetic phytoplankton which inhabit areas of light but are also susceptible to predation in high light. This describes the idea that A. franciscana require a fine balance of light in its environment to be able to feed without predation and therefore will show preference. Furthermore, the results of the pH treatment are also supported by Dhaheri (2004) who reported that A. franciscana can survive pH ranges between 7 and 10 with 8 being ideal for cysts (eggs) to