Impact of Microgravity Environment on Body Mass: Case Study of Lizards

Paul O. Jaiyeola, Funmilola A. Oluwafemi, Augustine O. Otum, Oladunjoye S. Tomori, Irene E. Bemibo, Abdullahi Ayegba

Microgravity, Simulated Microgravity, Body mass, Lizards.

Studies of animal behavior on spaceflight had shown that animals could survive trips away from the earth. This study examined the impact of microgravity environment on the body mass of lizards. Data was collected from the experiment conducted at the Microgravity Simulations Laboratory of the Engineering and Space Systems (ESS) Department, National Space Research and Development Agency (NASRDA), Abuja, Nigeria. A 2D clinostat was used as the microgravity simulations device. Three lizards were used for this experiment; sample A and sample B with body mass 7.5g and 8.0g respectively were impacted with simulated microgravity, while sample C (control) of body mass 7.2g was under normal earth gravitational influence. The data collected of their body masses after a period of observation was analyzed using regression analysis with other mathematical analyses. Resorptions were discovered in the body mass of samples A and B. Resorption increased as the period of microgravity simulations increased and lizard B being heavier than lizard A in body mass (equivalent to bone mass) had slower rate of resorption. The rate at which bone and muscles (body) mass declined under simulated microgravity was inversely proportional to the body mass. The non-linear curve therefore provides the most accurate and realistic comparative analysis for sample A and B as it gave realistic evidence that the sample A lizard had more body mass loss than lizard of sample B. The angle of rotation of the femur at midstance increased as the period of flight increased due to decrease in body mass. The decline in body mass of lizard samples A and B was more than lizard sample C, because sample A and sample B were under the influence of microgravity. Following non-linear body mass loss, it was agreed that the control lizard had little or no evidence of body mass loss since the non-linear curve is approximately parallel to the horizontal axis. Homeostatic stage was attained with sample A and sample B, with sample A 4.3g at t (2) and sample B with 4.5g at t (3) i.e. the lizard of greater body mass attained homeostatic stage later than the smaller body mass and that the linear regression analysis gave no indication of homeostatic, but the non-linear regression indicated homeostatic.

https://dx.doi.org/10.31873/IJEAS.7.08.03