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Once outside of the water； these animals gradually adapted
themselves more and more to life on land。 Some became reptiles
（creatures who crawl like lizards） and they shared the
silence of the forests with the insects。 That they might move
faster through the soft soil； they improved upon their legs
and their size increased until the world was populated with
gigantic forms （which the hand…books of biology list under
the names of Ichthyosaurus and Megalosaurus and Brontosaurus）
who grew to be thirty to forty feet long and who could have
played with elephants as a full grown cat plays with her kittens。
Some of the members of this reptilian family began to live in
the tops of the trees； which were then often more than a hundred
feet high。 They no longer needed their legs for the purpose
of walking； but it was necessary for them to move quickly from
branch to branch。 And so they changed a part of their skin
into a sort of parachute； which stretched between the sides of
their bodies and the small toes of their fore…feet； and gradually
they covered this skinny parachute with feathers and made
their tails into a steering gear and flew from tree to tree and
developed into true birds。
Then a strange thing happened。 All the gigantic reptiles
died within a short time。 We do not know the reason。 Perhaps
it was due to a sudden change in climate。 Perhaps they
had grown so large that they could neither swim nor walk nor
crawl； and they starved to death within sight but not within
reach of the big ferns and trees。 Whatever the cause； the
million year old world…empire of the big reptiles was over。
The world now began to be occupied by very different
creatures。 They were the descendants of the reptiles but they
were quite unlike these because they fed their young from the
‘‘mammae'' or the breasts of the mother。 Wherefore modern
science calls these animals ‘‘mammals。'' They had shed the
scales of the fish。 They did not adopt the feathers of the bird；
but they covered their bodies with hair。 The mammals however
developed other habits which gave their race a great advantage
over the other animals。 The female of the species
carried the eggs of the young inside her body until they were
hatched and while all other living beings； up to that time； had
left their children exposed to the dangers of cold and heat；
and the attacks of wild beasts； the mammals kept their young
with them for a long time and sheltered them while they were
still too weak to fight their enemies。 In this way the young
mammals were given a much better chance to survive； because
they learned many things from their mothers； as you will know
if you have ever watched a cat teaching her kittens to take
care of themselves and how to wash their faces and how to
catch mice。
But of these mammals I need not tell you much for you
know them well。 They surround you on all sides。 They are
your daily companions in the streets and in your home； and you
can see your less familiar cousins behind the bars of the zoological
garden。
And now we come to the parting of the ways when man
suddenly leaves the endless procession of dumbly living and
dying creatures and begins to use his reason to shape the
destiny of his race。
One mammal in particular seemed to surpass all others in
its ability to find food and shelter。 It had learned to use its
fore…feet for the purpose of holding its prey； and by dint of
practice it had developed a hand…like claw。 After innumerable
attempts it had learned how to balance the whole of the
body upon the hind legs。 （This is a difficult act； which every
child has to learn anew although the human race has been
doing it for over a million years。）
This creature； half ape and half monkey but superior to
both； became the most successful hunter and could make a
living in every clime。 For greater safety； it usually moved
about in groups。 It learned how to make strange grunts to
warn its young of approaching danger and after many hundreds
of thousands of years it began to use these throaty noises
for the purpose of talking。
This creature； though you may hardly believe it； was your
first ‘‘man…like'' ancestor。
OUR EARLIEST ANCESTORS
WE know very little about the first ‘‘true'' men。 We have
never seen their pictures。 In the deepest layer of clay of an
ancient soil we have sometimes found pieces of their bones。
These lay buried amidst the broken skeletons of other animals
that have long since disappeared from the face of the earth。
Anthropologists （learned scientists who devote their lives to
the study of man as a member of the animal kingdom） have
taken these bones and they have been able to reconstruct our
earliest ancestors with a fair degree of accuracy。
The great…great…grandfather of the human race was a very
ugly and unattractive mammal。 He was quite small； much
smaller than the people of today。 The heat of the sun and the
biting wind of the cold winter had coloured his skin a dark
brown。 His head and most of his body； his arms and legs too；
were covered with long； coarse hair。 He had very thin but
strong fingers which made his hands look like those of a monkey。
His forehead was low and his jaw was like the jaw of a
wild animal which uses its teeth both as fork and knife。 He
wore no clothes。 He had seen no fire except the flames of the
rumbling volcanoes which filled the earth with their smoke
and their lava。
He lived in the damp blackness of vast forests； as the
pygmies of Africa do to this very day。 When he felt the
pangs of hunger he ate raw leaves and the roots of plants or
he took the eggs away from an angry bird and fed them to his
own young。 Once in a while； after a long and patient chase；
he would catch a sparrow or a small wild dog or perhaps a
rabbit。 These he would eat raw for he had never discovered
that food tasted better when it was cooked。
During the hours of day； this primitive human being
prowled about looking for things to eat。
When night descended upon the earth； he hid his wife and
his children in a hollow tree or behind some heavy boulders；
for he was surrounded on all sides by ferocious animals and
when it was dark these animals began to prowl about； looking
for something to eat for their mates and their own young； and
they liked the taste of human beings。 It was a world where
you must either eat or be eaten； and life was very unhappy
because it was full of fear and misery。
In summer； man was exposed to the scorching rays of the
sun； and during the winter his children would freeze to death
in his arms。 When such a creature hurt itself； （and hunting
animals are forever breaking their bones or spraining their
ankles） he had no one to take care of him and he must die a
horrible death。
Like many of the animals who fill the Zoo with their
strange noises； early man liked to jabber。 That is to say； he
endlessly repeated the same unintel