Transcript Amazing Biodiversity

Earth – The LIVING Planet!
Where is life found?
Between 5 - 30 Million species (who knows?!), located in 867
distinctly different “life zones”
WHY is each zone so different from the others?!
Life is extremely DIVERSE – can you
categorize or classify any of these animals?
• How is this
Greyhound different
from a regular
Greyhound?
• What caused this
“change”?
– Clue 1: it’s not from
working out…
– Clue 2: it was born
this way…
Earth is “just right” for life
• Earth is located in the “habitable zone” around a star, and travels in its
orbit around the Sun (a distance of 600 million miles!). It’s size and
gravitational force causes it to veer from a straight line only one-ninth
of an inch every eighteen miles. If it veered by one-tenth of an inch
away, the orbit would become so large that life on the Earth would be
impossible due to drastically-reduced temperatures; if it veered by
one-eighth of an inch toward, life on the Earth would be impossible due
to drastically-increased temperatures. One-ninth of an inch – just right!
• The Earth completes its orbit in about 365 days—which represents
what we call one year. This, together with the fact that the Earth is tilted
on its axis, allows for what we call "seasons." The rotation of the Earth
on its axis, (stabilized by our Moon – which also causes the vital tides
of the ocean), provides periods of light and darkness, which is
necessary to sustain life as we know it. Without the tilt, most of our
planet would either bake or freeze. If the Earth rotated much faster,
fierce hurricanes would stir over the Earth like a kitchen food mixer. If
the Earth turned significantly slower, the days and nights would be
impossibly hot or cold. Venus, for example, turns only once every 243
days, which accounts in part for the fact that daytime temperatures can
reach as high as 500 degrees Celsius (water boils at 100 degrees). 365
days, with a moon and a tilted axis – just right!
• Wrapped around the Earth, and about 90 miles deep,
is a protective blanket of gasses we know as the
atmosphere. The proper balance of these gases is
essential to life on the Earth. The atmosphere of
Venus is too thick to sustain life; that of Mars is too
thin. But the Earth’s atmosphere does several
things. Without water vapor and certain gases, the
heat would escape as soon as the Sun set each day,
& we would freeze every night. Were it not for the
fact that most meteors burn up (from friction) when
they strike the thick atmosphere, the Earth would be
pounded almost daily by these unwelcome visitors.
Between 6-30 miles above the Earth, the ozone layer
filters out most of the ultraviolet rays from the Sun
that would be harmful to life’s DNA, and fatal in
larger amounts. Earth is also one of the few planets
that has plentiful liquid water – essential to all living
things. 90 miles of uniquely composed atmosphere,
with liquid water – just right!
• “The laws of science, as we know them at
present, contain many fundamental
numbers, like the size of the electric charge
of the electron and the ratio of the masses
of the proton and the electron …. The
remarkable fact is that the values of these
numbers seem to have been finely adjusted
to make possible the development of life.”
– Stephen Hawking
• “The more I examine the universe and the
details of its architecture, the more evidence
I find that the universe in some sense must
have known we were coming…”
– Freeman Dyson
Disturbing the Universe
New York: Harper & Row, 1979, p. 250