Observing Crickets Giving Birth In Space
Ulm, Germany (SPX) May 18, 2005
It was strange music to the ears of Italian astronaut Roberto
Vittori on his taxi flight to the ISS, accompanied by 14 female
house crickets for the CRISP 2 biology experiment, proposed by Ulm
University and managed for ESA by CNES and CADMOS.
This is the story of an experiment using these surprising insects
to help us better understand the effects of gravity on neuron
proliferation.
The CRISP 2 science experiment was flown as part of the Italian
Eneide mission on the ISS.
Its objective was to measure the effects of gravity on neuron
proliferation, because although neuron development is genetically
controlled it also responds to the surrounding environment.
The experiment used female house crickets (Acheta
domesticus).
Crickets have sensors at the end of their abdomen, on their head
and on other parts of their body through which they sense gravity
to orient themselves. What happens if young larvae develop in
microgravity?
Will the connections between the animal's brain and its gravity
sensors form? How will the crickets behave on returning to a normal
gravity environment on Earth?
An initial experiment in 1998 showed that the response of cricket
larvae to gravity was not affected by a period in microgravity. On
the other hand, the neurons linked to their positional sensors were
altered. But this experiment used young larvae that had grown on
Earth.
To allow them to develop in microgravity, the larvae used as test
specimens for CRISP 2 were inseminated in a ground laboratory and
left to deposit their eggs on board the ISS.
CRISP 2 was supervised by CNES's CADMOS centre for the development
of microgravity applications and space operations. CADMOS's role is
to provide technical and operations support to science teams for
microgravity experiments.
On this mission, it oversaw development of equipment at Ulm
University, produced documentation and supervised astronaut
training on CRISP and mission simulation.
After this preparatory phase, the 14 female crickets were placed in
the Soyuz spacecraft. On board, they were transferred to ESA's
KUBIK incubator with the internal temperature set at 28 °C.
The females were allowed to deposit two batches of eggs at
different times, to obtain young larvae at the start of the mission
and more fully developed ones at the end.
The crickets' behaviour was recorded on 4 videos for subsequent
study. A control experiment was conducted at the same time in a
ground laboratory using identical equipment, for comparison with
the results obtained in microgravity.
Once the mission was over, CNES recovered the female crickets and
larvae for transfer to Germany.
The females were able to make the trip at a controlled temperature
with the help of Air France, which allowed these unusual passengers
to travel in a temperature-controller container in the cabin.
And border police were happy to let the "young mothers" through
without subjecting them to X-ray screening.