Since the dawn of the space age in the last century, humans have sent animals into the nether regions to find out if living creatures could survive, to test for various benefits and risks for us humans. It is the way One Health uniquely integrates animals and environmental concerns, in a multidisciplinary context.
We need to recognize that these animals are our explorers, our pathfinders, and heroes even if it isn’t by their choice.
To be sure, the use of animals to test human survival in space has caused controversy: Even though animals have been successfully used to pave the way for space exploration, without in most cases loss of life or hurting the animal, many feel this is the wrong approach, that other methods should be used – the argument is that animals have no choice in the matter and therefore should not be used for testing.
There are, however, testing procedures using animals that are not harmful to the animal and yet result in insightful findings that make for important scientific progress that ultimately benefits not only humans but also animals. Indeed, now new experiments are carried out here on Earth – at least those carried out in the West. While there is much talk of NASA and Elon Musk’s Space X collaboration to go on Mars, nobody is suggesting that dogs go to Mars with the astronauts as their pets.
Significantly, NASA is launching this year a simulation of space living here on Earth and the four selected “astronauts” for the experiment will live in close quarters for a whole year – a 158-square-meter station in the Texan desert – without any pet animal to keep them company.
Here, we shall look at how research into animal survival under extreme conditions, first in space and more recently on Earth, is helping us not only to reach the stars but also to improve life for humans, here and now.
From the first exploratory days: Animals in space without restraint
Animals in space originally served us to test the survivability of spaceflight, well before human spaceflights were attempted.
The first animals in space were insects. In 1947 fruit flies were put on a U.S. V-2 rocket to test the effects of radiation at high altitudes on a living creature. Reaching an altitude of 109 kilometers, the capsule carrying the flies was ejected, parachuted back to Earth, and it showed they were able to remain intact and alive.
Thereafter, a wide variety of animals were launched into space, including monkeys and apes, dogs, cats, tortoises, mice, rats, rabbits, fish, frogs, spiders, and other insects. Laika, a stray dog from the streets of Moscow, was the first animal to orbit the earth in the Soviet spacecraft Sputnik 2 in 1957:
As shown in the above video, a sampling includes two tortoises and a variety of insects that were the first inhabitants from Earth to circle the Moon in 1968. In 1972 five mice, Fe, Fi, Fo, Fum, and Phooey “accompanied” the US Apollo crew in orbiting the Moon for a record 75 times.
To date, seven national space programs have flown animals into space including the Soviet Union (Russian Federation), United States, France, Argentina, China, Japan, and Iran.
Experiments already done or ongoing
The range of studies that rely on animals to garner critical information for human-planned space travel and in understanding our environment is simply breathtaking; and it hasn’t been limited to experiments in space but moved to a wide range of studies here on Earth, thus broadening the scope of the research.
Research has also been boosted by successful international collaboration, notably on the International Space Station (ISS).
For example, the “International Cooperation for Animal Research Using Space Project” (ICARUS) tracks migratory bird patterns from ISS in order to provide information on natural disasters and infectious diseases.
This is far from a purely academic exercise: The course of the growing outbreak of Avian Flu may benefit from these efforts, an example of how the view from space can assist in addressing earthly problems.
As to understanding the impact on humans of future space travel to Mars or living for extended periods on the moon, the field is exploding with research and experiments. Here are a few notable examples.
Effects from extended space flight on muscle use and bone loss
While it is virtually impossible on Earth to approximate the partial gravity of Mars, researchers have developed a partial-gravity model to test rodents in a Moon and Mars simulation.
An experimental facility has been designed to re-create the partial gravity environment using rats as human analogs. These animals, partially suspended with a harness system, were thus placed in a condition inducing muscle disuse atrophy and bone mineral density reductions similar to space travel, with the objective to learn about the effects of microgravity on people in space.
This experiment exposed mice to different levels that astronauts would encounter on long-duration terrestrial spaceflight missions; they were subjected to specific antibody treatments to prevent or contain the damaging effects.
The results demonstrated that this therapy could be of benefit in preventing astronaut bone loss during terrestrial solar system exploration.
Spaceflight changes to the brain
The analysis of the brains of mice flown in space for 13 days found significant changes related to neuron structure and metabolic function that could, in time, lead to injury and neurodegeneration.
This suggests that spaceflight affects the brain negatively at a cellular level and that countermeasures to protect brain function may be needed.
How space flight affects human immune systems
The fruit fly has been used extensively to study biological processes, including genetics and physiology. One such important area of study is fruit fly immunity.
Fruit flies have an innate immune system similar to that of humans, which acts as the “first responder” to defend an organism from initial infection by a foreign pathogen.
NASA-funded studies of immune cells have shown that spaceflight alters immune function.
Wasps lay their eggs into the fly larvae which induce a fly larval immune response against the wasp larvae and eggs, similar to a response to bacterial infection.
Continuing research is looking into how the space environment affects the fruit fly’s anti-parasitic immune response to the wasp pathogen where the fruit fly lays its eggs It will determine if the parasitic virulence of the space-cultured wasps is different from the ground control wasps.
The results will provide insight into how long-duration spaceflight impacts a key immune response mechanism and pathogen infection. This may lead to a greater understanding of how the spaceflight environment alters human innate immunity.
There are space research projects looking into which non-human species can survive and which do poorly.
For example, space-bound spiders learned to spin their webs without the benefit of gravity, while crickets failed to develop the organs that usually assist with their sense of balance. With no ‘up’ or ‘down,’ Mummichog minnows initially pitched forward and swam in tight circle.
Extreme survival: Finding lessons from animals adapted to the most extreme environments on Earth
Among the most fascinating animals adapted to extreme environments are tardigrades. They are microscopic, multicellular animals that can live for decades without food or water and survive temperature extremes from near absolute zero to well above the boiling point of water.
Tardigrades have been known to survive a number of extreme stresses, including desiccation, freezing, and boiling temperatures, intense ionizing radiation, and extremes in pressure—including the vacuum of outer space.
A new study will examine the cellular adaptions to the extremes of space. This new experiment will seek to identify genes that respond to and are required for tardigrades to survive different stress conditions, examine both immediate and long-term, multigenerational changes onboard the International Space Station.
One day these experiments may lead to the development of ways to provide food for space travelers. The expectation is that more drought- and temperature-resistant crops and new methods for stabilizing sensitive pharmaceuticals and other biological materials will be found.
Feeding people on the Moon or Mars
At the French Research Institute for Exploitation of the Sea, a researcher, Cyrille Przbyla’s current project is the “Lunar Hatch Programme.” This groundbreaking project involves determining if fish eggs would hatch after enduring simulated effects of a rocket launch and space flight. If they were to do so, the theory is fish eggs could then be brought to a future Moon base, hatched in an aquaculture system, and become a vital source of protein for deep space residents and other extraterrestrial dwellers.
Przybyla is convinced that the future of human spaceflight will feature plants, animals, and other organisms. He points to the 1972 film Silent Running, in which giant spaceships with greenhouse-like domes preserve a collection of plant and animal species in a future era when Earth’s forests have almost gone extinct.”
This is just the beginning
It is certain animal research in space will benefit both our knowledge of how humans will need to cope as well as what can be learned about our environment on Earth from such animal research efforts.
From May 27-29, 2022, the next gathering of the International Space Development Conference will take place. Attendees include space leaders, astronauts, scientists, and others interested. You can be sure that the animal/human/ecosystem nexus will be on the agenda given its vision:
“People living and working in thriving communities beyond the Earth, and the use of the vast resources of space for the dramatic betterment of humanity.”
In short, one thing is certain: The “dramatic betterment of humanity” cannot be achieved without help from animal research – proving once again, that the One Health approach is essential.
Perhaps one of the most groundbreaking results of this space research effort will come from observations here on Earth of those rare organisms living under the most extreme space-like conditions. One can expect that they will allow scientists to come closer to answering what is perhaps the most basic question of all: What is “life” and what defines the limits between life and non-life?
This definition is absolutely necessary because, without knowing precisely what we are looking for when we “search for life” on other planets, we won’t know “life” when we see it.
Editor’s Note: The opinions expressed here by Impakter.com columnists are their own, not those of Impakter.com — In the Featured Photo: Spider weaving a web in space Source: NASA article April 23, 2014