It isn't just humans, apes, dolphins, birds, and octopuses who use tools. Even fish have been spied using rocks to break open shellfish -- and now a video of an orange-dotted tuskfish doing just that is available to prove the claim.
WASHINGTON — US astronomers said Wednesday they have discovered an Earth-sized planet that they think might be habitable, orbiting a nearby star, and believe there could be many more planets like it in space.
