Barnell Bohusk has lived a difficult life since his mutation first manifested. Always wanting to find a better life, Barnell threw himself into his studies at Xavier's. He also befriended the Beast, finding a common bond with the X-Man with the most severe physical mutation. It was this bond that led him to visit the Beast with a gift, a baseball bat. Horribly, Beak was mentally possessed by a Cassandra Nova-controlled Charles Xavier and forced to beat his mentor brutally. The Beast would eventually recover, but Beak's guilt never went away.
Mocked by his peers at the Xavier Institute for his seemingly useless mutation, Beak gravitated towards a group of young mutants known as the special class - mutants with little drive and less ability. Ironically, in this class Beak truly began to realize his worth as a hero. The other special class students began to look up to him as a leader and he filled that role as best he could. This group also included his girlfriend and the mother of his children, Angel. Angel does care for Beak, but their relationship began when other students bet her to kiss him.
This group was mentored by Xorn who secretly believed he was truly Magneto. Beak and the rest of his special class followed Xorn, becoming the new Brotherhood in his bid to take over of the world. Beak stood up to Xorn and was cast out of the Brotherhood. He and a small group of X-Men were able to overtake Xorn and free New York City from his grip. Beak returned to the Xavier Institute and moved into a small home on campus with Angel and their children.
Soon after, the Exiles arrived at the Xavier Institute and Beak was forced to join their reality-fixing group. He left Angel and his children behind, unable to say goodbye to them. Angel assumed he deserted her.
After a number of adventures with the Exiles, Beak was reunited with Angel when they visited the Earth while it was under the sway of the House of M|Scarlet Witch's reality warp. Upon the reversal of this warp Beak lost his mutant powers and is currently living the life of a normal human.