Many animals, particularly primates, have been sent into space since the 1940s. The original premise of sending monkeys into space was to test their ability to withstand weightlessness, which was a primary concern about sending humans into space, according to NASA.
The first monkey launch was on June 11, 1948. Several additional missions with monkeys were launched over the next few years. Most of the primates died during launch, on impact or during the descent in those initial years of test launches. Many primates launched since that point have died as well, though some have survived their missions. Regardless, these test launches have provided valuable data leading up to human space missions.