The scollopide you had, had a hiden ability. In gen 5 Scollopides hidden ability is quick feet. In gen 6 however Scollopides hidden ability became Speed Boost. When you sent your gen 5 scollopide to a gen 6/7 game the gaem updated the scollopide to match the game. That is how the scollopides ability became speed boost. Under stand?