When was the lock with 10 caps born?
CREATE TABLE "2007_rugby_world_cup_squads" (
  "player" text,
  "position" text,
  "date_of_birth_age" text,
  "caps" real,
  "club_province" text
);
SELECT "date_of_birth_age" FROM "2007_rugby_world_cup_squads" WHERE "position"='lock' AND "caps"=10;