http:www'picturehistory'comproductid15157

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HMS Beagle

• The second voyage of HMS Beagle from 27 December
  1831 to 2 October 1836 was the second survey
  expedition of HMS Beagle
• Captain Robert FitzRoy accompanied by a student
  clergyman Charles Darwin
• Darwin made his name as a naturalist and became
  a renowned author with the publication of his
  journal which became known as The Voyage of the
  Beagle.
• The Beagle sailed across the Atlantic Ocean then
  carried out detailed hydrographic surveys around
  the coasts of the southern part of South America,
  returning via Tahiti and Australia having
  circumnavigated the Earth. While the expedition
  was originally planned to last two years, it
  lasted almost five.

• Born 12 Feb 1809
• Medicine (Edinburgh University), Theology
  (Cambridge)
• 1859, publication of The Origin of Species

http//en.wikipedia.org/wiki/Evolution
http//www.picturehistory.com/product/id/15157
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The natural history of these islands is
eminently curious, and well deserves attention.
Most of the organic productions are aboriginal
creations, found nowhere else there is even a
difference between the inhabitants of the
different islands yet all show a marked
relationship with those of America, though
separated from that continent by an open space of
ocean, between 500 and 600 miles in width. The
archipelago is a little world within itself, or
rather a satellite attached to America, whence it
has derived a few stray colonists, and has
received the general character of its indigenous
productions.
The Galapagos Account
The Beagle sailed round Chatham Island, and
anchored in several bays. One night I slept on
shore on a part of the island, where black
truncated cones were extraordinarily numerous
from one small eminence I counted sixty of them,
all surmounted by craters more or less perfect.
The greater number consisted merely of a ring of
red scoriae or slags, cemented together and
their height above the plain of lava was not more
than from fifty to a hundred feet none had been
very lately active.
Download The Voyage of The Beagle from Project
Gutenberg http//www.gutenberg.org/wiki/Main_Page
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We will now turn to the order of reptiles, which
gives the most striking character to the zoology
of these islands. The species are not numerous,
but the numbers of individuals of each species
are extraordinarily great.

• Darwins Checklist
• Frogs none!
• Toads none!
• Lizards
• Tortoises

I have not as yet noticed by far the most
remarkable feature in the natural history of this
archipelago it is, that the different islands to
a considerable extent are inhabited by a
different set of beings. My attention was first
called to this fact by the Vice-Governor, Mr.
Lawson, declaring that the tortoises differed
from the different islands, and that he could
with certainty tell from which island any one was
brought.
Diet Adaptation
http//www.honoluluzoo.org/galapagos_tortoise.htm
Nesting Activity
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When on board H.M.S. Beagle, as naturalist, I
was much struck with certain facts in the
distribution of the organic beings inhabiting
South America, and in the geological relations of
the present to the past inhabitants of that
continent. These facts, as will be seen in the
latter chapters of this volume, seemed to throw
some light on the origin of speciesthat mystery
of mysteries, as it has been called by one of our
greatest philosophers. On my return home, it
occurred to me, in 1837, that something might
perhaps be made out on this question by patiently
accumulating and reflecting on all sorts of facts
which could possibly have any bearing on it.
After five years' work I allowed myself to
speculate on the subject, and drew up some short
notes
Introduction, The Origin of The Species
5
http//en.wikipedia.org/wiki/The_Origin_of_Species
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Natural Selection

• Predator-Prey
• Survival of the Fittest

http//www.essexwt.org.uk/leaflets/bee_gardening.h
tm

• Transmission of Traits

http//www.defenders.org/wildlife_and_habitat/wild
life/wolf,_gray.php
7
We behold the face of nature bright with
gladness, we often see superabundance of food we
do not see or we forget that the birds which are
idly singing round us mostly live on insects or
seeds, and are thus constantly destroying life
or we forget how largely these songsters, or
their eggs, or their nestlings, are destroyed by
birds and beasts of prey we do not always bear
in mind, that, though food may be now
superabundant, it is not so at all seasons of
each recurring year. Darwin, on discussing the
struggle for existence in The Origin of Species
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• To keep our model simple, we will make some
  assumptions that would be unrealistic in most of
  these predator-prey situations.
• the predator species is totally dependent on a
  single prey species as its only food supply,
• the prey species has an unlimited food supply,
  and
• there is no threat to the prey other than the
  specific predator.

• lions and gazelles
• birds and insects
• pandas and eucalyptus trees
• Venus fly traps and flies

http//www.math.duke.edu/education/ccp/materials/d
iffeq/predprey/pred1.html
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Percentages of predators in the Fiume fish catch
Vito Volterra (1860-1940) was a famous Italian
mathematician who retired from a distinguished
career in pure mathematics in the early 1920s.
His son-in-law, Humberto D'Ancona, was a
biologist who studied the populations of various
species of fish in the Adriatic Sea. In 1926
D'Ancona completed a statistical study of the
numbers of each species sold on the fish markets
of three ports Fiume, Trieste, and Venice. The
percentages of predator species (sharks, skates,
rays, etc.) in the Fiume catch are shown in the
above table. Alfred J. Lotka (1880-1949) was an
American mathematical biologist (and later
actuary) who formulated many of the same models
as Volterra, independently and at about the same
time. His primary example of a predator-prey
system comprised a plant population and an
herbivorous animal dependent on that plant for
food.
http//www-groups.dcs.st-and.ac.uk/history/PictDi
splay/Volterra.html
http//www.math.duke.edu/education/ccp/materials/d
iffeq/predprey/pred2.html
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Prey Population x(t) No predators dx/dt a
x Predators exist Predator Population
y(t) Encounters jointly proportional to xy
Thus ? dx/dt ax bxy Lets consider the
predators y(t). No prey means dy/dt ?cy But
with food dy/dt ?cy pxy
dx/dt ax bxy dy/dt ?cy pxy