Australia Is The Most Isolated Continent.

Bird Taxonomy Is A Difficult Field Because Of The Severe Anatomical Constraints Imposed By Flight. There Are Only So Many Ways To Design A Bird Capable, Say, Of Catching Insects In Mid-air, With The Result That Birds Of Similar Habitats Tend To Have Very Similar Anatomies, Whatever Their Ancestry. For Example, American Vultures Look And Behave Much Like Old World Vultures, But Biologists Have Come To Realize That The Former Are Related To Storks, The Latter To Hawks, And That Their Resemblances Result From Their Common Lifestyle.

Besides Justifying The Transfer Of Wealth To Kleptocrats, Institutionalized Religion Brings Two Other Important Benefits To Centralized Societies. First, Shared Ideology Or Religion Helps Solve The Problem Of How Unrelated Individuals Are To Live Together Without Killing Each Other—by Providing Them With A Bond Not Based On Kinship. Second, It Gives People A Motive, Other Than Genetic Self-interest, For Sacrificing Their Lives On Behalf Of Others.

Although Native Africans Domesticated Some Plants In The Sahel And In Ethiopia And In Tropical West Africa, They Acquired Valuable Domestic Animals Only Later, From The North.

Much Of Human History Has Consisted Of Unequal Conflicts Between The Haves And The Have-nots.

But This Was The Only Way Of Life That Humans Knew For Their First 6m Years On The Planet. In Giving It Up Over The Past Few Thousand Years, We Have Lost Our Vulnerability To Disease And Cold And Wild Animals, But We Have Also Lost Good Ways To Bring Up Children, Look After Old People, Stave Off Diabetes And Heart Disease And Understand The Real Dangers Of Everyday Life.