Article continues below advertisementJane Goodall's official cause of death has been revealed less than one month after her sad passing.The famed conservationist died from cardiac arrest, also known as cardiopulmonary arrest, according to a death certificate obtained by TMZ.Goodall was found dead in her sleep in Los Angeles at age 91 on October 1.Article continues below advertisementJane Goodall Died 'Peacefully' From Cardiac ArrestSource: MEGAJane Goodall's cause of death was cardiac arrest.