Research Intro- Impact of Temperature and Light Exposure on Growth Rate of Mealworms by Josselin Chambily, Bishoy Galil, Travis Friesner, Hiu Nam (Tiger) Wong

Impact of Temperature and Light Exposure on Growth Rate of Mealworms

Group members: Josselin Chambily, Travis Friesner, Bishoy Galil, Hiu Nam Wong

Figure 1. Flow chart indicating life cycle of a mealworm.

Tenebrio molitor, commonly known as mealworms, are classified as Arthropods mainly due to their segmented body structure. The life cycle of mealworms consist of four stages. First, the eggs laid by beetles will hatch and become larvas. Then, the larvae will grow for about 1-4 weeks and develop into pupae, which eventually mature into beetles and the cycle repeats. According to Glenn Kvassay, the larval developmental stage of a mealworm is a fast process where newly hatched mealworms are 3 mm long and grow quickly into about 3 cm mealworms (Kvassay 2017). This short and rapid growth period of mealworms lasts around 2 weeks and allows us to explore how different factors will cause distinct impact on the growth rate. In relation to that, a paper published by the University of Nebraska-Lincoln suggests that larval development is influenced by temperature, relative humidity and more. They found out that it takes about 80 days for mealworms to emerge from eggs into adult beetles, given the condition at 30oC and 55% relative humidity (University of Nebraska-Lincoln). Another research conducted by a few STU Bed students adds a new perspective on preferences of mealworms during their growth period. In which the group explored whether mealworms prefer light or dark places by observing their behavior in an environment with both light and dark spots, and their results shows that the mealworms in general avoid the lighter locations (Boyle et al. 2011). These intriguing findings led us to think about what is the optimum temperature for mealworms growth, and does exposure to light affect their growth rate causing mealworms to avoid light spots. In other words, we hope to find out how the growth rate of mealworms is impacted by temperature and exposition to light. For our experiments, mealworms will be put under different temperatures, and exposed to different light sources. Then, the growth of mealworms will be accessed with length and weight of our samples. Previous researches found out that the optimum condition for mealworms growth to be in the dark at 72oF (~22oC). Accordingly, we will have mealworms exposed to light grow under 72oF or 68 oF (~20 oC), and mealworms that are kept in dark placed under the two temperatures.

We hypothesize that temperature and light will have an effect on the growth rate of mealworms. Testing this hypothesis we want our research to find out what factors contribute to their ideal habitat. Moreover, we predicted that mealworms that are nurtured in the dark at 72oF will grow the fastest compared to mealworms put under different conditions. As a result, the main question for our project is how temperature and light impact rate of growth of mealworms.

For our animal biology class, we are looking for the effects of different stimuli on the growth and responses of animals. This research project is very interesting helping us to measure the effect of temperature and light on the rate of growth of mealworms. Our independent variable for this experiment is the change of temperature and light sources, and our dependent variable is the rate of growth for our sample mealworms. We decided to do this research project because it is challenging, as there are many other factors than temperature that can affect the rate of growth. We decided that we will measure the rate of growth by measuring the mass and the length of the mealworms after certain periods.We are still discussing if we can use the kind of diet as another independent variable, but we are not sure if that we be effective.

Coming up with a research topic is tough, one major challenge is to identify all the possible errors or obstacles. In order to have a feasible experiment, we have to think thoroughly about any limitations, like the cost of the experiment subject, required time for the experiment, and the measurements of variables. For example, we intended to do a research on how acidity of water impact limb regeneration of newts, but after some primary research, the cost of newts is too high and there is not enough time for newts to grow significantly plus obtain great measurements. In addition, a permit is required to work with vertebrates so that means a big NO for this topic. With the current topic, we believe it is still very interesting and at the same time more feasible.  

Reference Citation

Boyle, Catherine, Gallie, Kelly, Sampson, Elise, Smith, Nicole. Experiment 3 Dark vs Light. 2011: Mealworm Guided Discovery; [accessed 2018 Feb 8]. https://mealworms2011.wikispaces.com/Experiment+3+-+Dark+vs.+Light.

Kvassay, Glenn. Successful Mealworms Breeding is Having a Good Understanding of Their Lifecycle. 2017: Wild Life Hub; [accessed 2018 Feb 8]. https://wildlifehub.com/mealworm-life-cycle/.

Mealworm Metamorphosis: Effect of Temperature (development). : University of Nebraska-Lincoln; [accessed 2018 Feb 8]. https://entomology.unl.edu/k12/mealworms/development.htm.