Complex sentence: Granny (born c.1911, presumed dead January 2017), also known as J2, was an orca, or killer whale, estimated by some whale researchers to have been 105 ± 12 years old.
Split into simpler sentences: Granny (born c.1911, presumed dead January 2017), also known as J2, was an orca (killer whale). She was estimated by some whale researchers to have been 105 ± 12 years old.