Notice in the gorilla's skull the protrusive face region, the big eyebrow ridges, the much less domed cranial cavity, the massive lower jaw, the big canine teeth. Notice in man's skull the well-developed forehead, the domed and spacious cranial cavity, the absence of any snout, the chin process, and many other marked differences separating the human skull from the ape's.] [Illustration: THE SKULL AND BRAIN-CASE OF PITHECANTHROPUS, THE JAVA APE-MAN, AS RESTORED. BY J. H. McGREGOR FROM THE SCANTY REMAINS The restoration shows the low, retreating forehead and the prominent eyebrow ridges.] [Illustration: SUGGESTED GENEALOGICAL TREE OF MAN AND ANTHROPOID APES From Sir Arthur Keith; the lettering to the right has been slightly simplified.] We are on firmer, though still uncertain, ground when we state the probability that it was in Asia that the precursors of man were separated off from monkeys and apes, and began to be terrestrial rather than arboreal. Professor Lull points out that Asia is nearest to the oldest known human remains (in Java), and that Asia was the seat of the most ancient civilisations and the original home of many domesticated animals and cultivated plants. The probability is that the cradle of the human race was in Asia. Man's Arboreal Apprenticeship At this point it will be useful to consider man's arboreal apprenticeship and how he became a terrestrial journeyman. Professor Wood Jones has worked out very convincingly the thesis that man had no direct four-footed ancestry, but that the Primate stock to which he belongs was from its first divergence arboreal. He maintains that the leading peculiarities of the immediate precursors of man were wrought out during a long arboreal apprenticeship. The first great gain of arboreal life on bipedal erect lines (not after the quadrupedal fashion of tree-sloths, for instance) was the emancipation of the hand. The foot became the supporting and branch-gripping member, and the hand was set free to reach upward, to hang on by, to seize the fruit, to lift it and hold it to the mouth, and to hug the young one close to the breast. The hand thus set free has remained plastic--a generalised, not a specialised member. Much has followed from man's "handiness."