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Effect of Weightlessness on Development of Amphibian Eggs (178256)
Principal Investigator
Research Area:
Developmental biology
Species Studied
Scientific Name: Xenopus laevis Species: Frog, Tree Strain: South African three-clawed


On Earth the animal-vegetal axis of amphibian eggs will rotate upon fertilization to align with the gravitational field. This rotation plays a role in determining the polarity of the embryonic axis and may also influence normal development. In addition, eggs inclined with respect to gravity develop dorsal structures on the uppermost surface from the gravitational field. The objective of this experiment was to determine whether gravity is required for normal embryonic development. Prolific Xenopus laevis females were selected for flight.

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Black S, Larkin K, Souza K: Results from the frog embryology experiment: development of swimming tadpoles occurs at microgravity. ASGSB Bulletin, vol. 7(1), October 1993, pp. 32.

Black S, Larkin N, Jacqmotte N, Wassersug R, Pronych S, and Souza K: Regulative development of Xenopus Laevis in microgravity. Adv. Space Res., vol. 17 (6/7), 1996, pp. 209-217.

Fejtek M, Neff A, Souza K, Wassersug R: Gravitational effects on the locomotor behavior of hatching anuran larvae [abstract]. ASGSB Bulletin, vol. 6 (1), October 1992, pp. 46.

Fejtek M, Souza K, Neff A, and Wassersug R: Swimming kinematics and respiratory b ehaviour of Xenopus Laevis larvae raised in altered gravity. The Journal of Experimental Biology, 201, 1998, pp. 1917-1926.

Miquel J, Souza KA: Gravity effects on reproduction, development, and aging. Advances in Space Biology and Medicine, vol. 1, 1991, pp. 71-97.

Pronych SP, Souza KA, Neff AW, and Wassersug, RJ: Optomotor behaviour in Xenopus Laevis tadpoles as a measure of the effect of gravity on visual and vestibular neural integration. The Journal of Experimental Biology, 199, 1996, pp. 2689-2701.

Souza KA, Black SD, Wassersug RJ: Amphibian development in the virtual absence of gravity. Proceedings of National Academy of Science USA, vol. 92, March 1995, pp. 1975-1978.

Wassersug RJ, Izumi-Kurotani A, Yamashita M, Naitoh T: Motion sickness in amphibians. Behavioral Neuralogical Biology, vol. 60(1), July 1993, pp. 42-51.

Wassersug RJ, Souza KA: The bronchial diverticula of Xenopus larvae. Are they essential for hydrostatic assessment?. Naturwissenschaften, vol. 77(9), September 1990, pp. 443-445.

Photo Gallery
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Data Information
Data Availability
Archiving in Progress. Some data exist for this experiment.
Data Sets+ View data

Behavior, Swimming, tadpole, frog, Observation. videotape
Dorso-anterior differentiation
Fertilization rate
Optomotor behavior

Mission/Study Information
Mission Launch/Start Date Landing/End Date Duration
STS-47 09/12/1992 09/19/1992 7 days

Additional Information
Managing NASA Center
Ames Research Center (ARC)
Responsible NASA Representative
Ames Research Center LSDA Level 3
Project Manager: Martha Del Alto
Institutional Support
National Aeronautics and Space Administration (NASA)
Alternate Experiment Name
Protocol / Approach
Synchronous control
Delayed synchronous control
Proposal Source