Joshua Bat-Levi was a male Human born circa 2305. He was the twin brother of Darya Bat-Levi, and though only two minutes younger, referred to himself as the baby brother. His sister gave him the nickname "Jock-o".
Sometime prior to 2326, Darya theorized that vacuum energy could be harnessed from space and used to power warp drive vessels. Joshua built upon this theory and used it to design and build an experimental starship engine. In 2326, he had his engine installed into a modified Starfleet shuttlecraft, dubbed Lion, stationed at Starbase 32. By this time, Darya had graduated from Starfleet Academy, and prior to reporting for her first assignment, the USS Wheedon, traveled to Starbase 32 to help prepare the vessel for a test run.
Tragically, the engine malfunctioned, and as Joshua attempted to stop an energy overload, the ship exploded, killing him and severely injuring his sister. (ST - The Lost Era novel: Well of Souls)