Complex sentence: In 1973 the mummichog became the first fish in space when carried on Skylab 3 as part of the biological experiments package later space missions by the U.S., such as Bion 3, have also carried mummichog.
Split into simpler sentences: In 1973 the mummichog became the first fish in space when carried on Skylab 3 as part of the biological experiments package. Later space missions by the U.S., such as Bion 3, have also carried mummichog.