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    Last modified 09/27/08


        Copyright © by Nila Gaede 2008
The ecological
pyramid overturns:
a case study
Adapted for the Internet from:

Why God Doesn't Exist

    The basic food chain consists of three trophic levels: primary producers (plants), herbivores, and carnivores.  In a healthy
    or ‘normal’ food chain the higher level typically consumes 10% of the biomass of the level it feeds on. Drastic changes to
    these proportions lead to instability. We can expect the animals which depend on a source of food that is rapidly
    diminishing to run into a lot of trouble. The fossil record should then show a unique ‘conveyor belt’ pattern when a grand
    class of plants comes to an end.

    Visualize now the sub-system T-Rex – Triceratops – Cycadeoids some time in the Late Cretaceous (65 mya). The
    Triceratopses have grown in number because after millions of years they have finally managed to overcome pernicious
    diseases. They are not only more numerous, they are also larger and therefore hungrier. They had to develop size (and
    appetites) in response to their ongoing war with their enemies, the T-Rexes. The two species have been around for some
    time and have gradually adapted to each other. Only this explains why they are both so formidable.

    Unfortunately for the ceratopses, they have grown big and numerous at the wrong chronological moment. Just when the
    mighty herds are expanding in numbers as well as in size, the angiosperms have grown from lakes to oceans while the
    forests of Bennettitales have shrunk from seas to puddles. The rapidly radiating meadows of angiosperms have converted
    the once lush forests of cycads and cycadeoids into pitiful islands. The last terrestrial dino herbivores in this region are
    unwittingly trapped in shrinking islands (Fig. 1). They have trouble finding food and limit their populations accordingly
    through density-dependence mechanisms.

Fig. 1   Eco Pyramid Inversion
A normal ecological pyramid is structured so that a given level is about 10%
of the one it feeds on. Typically, a carnivore lives by eating herbivores which
feed on plants. Towards the very end of the life of a category of plants this
process is reversed. The ancient species of  plants  are  crowded  out  by new
breeds and devastated by the animals that feed on them, which have now
grown large and numerous. The ancient plants are attacked from both ends:
by incoming plants and by the large animals that feed on them. The island
shrinks, and the animals that depend on these plants are fated to disappear
with them.

    The most compelling evidence for the ecological pyramid theory is what is about to happen to Man. If, as I will show next,
    Man cannot avoid the collapse of his carrying capacity despite having super-intelligence and the ability to see ahead, we
    must conclude that this is the only intrinsic extinction mechanism that no other species could have avoided either. We
    can do something about an asteroid that decides to attack the Earth. We can do nothing about our economy.
Look! Please try to understand. There
was this horrific scientific accident and,
to make a long story short,
I am not a part of your food chain.

Fig. 1

    At some point there has to be a strategic crossover. The cycad/cycadeoid to Triceratops ratio locally dips below a critical
    level and the unwitting animals are in deep trouble. For them, it happens overnight, although they may have an intuitive
    feel before this crucial marker that they have difficulties finding food. Now the process goes into fast forward. We have
    the many feeding on the few and observe a rapid overturning of the local ecological pyramid (Fig. 2). The archaic
    gymnosperms are slaughtered left and right.

    Will the Triceratopses switch diets at the last moment, from cycads to grasses?

    Well, do you think you would begin eating tree leaves and weeds if you cannot find hamburgers and French fries around?
    Would you have ten children under these conditions?

    Meanwhile, the T-Rexes have also expanded demographically in proportion to the population of Triceratopses. This gives
    the plants a respite, but it is too little too late. The more versatile, upwardly mobile angiosperms are choking what's left of
    the empire of the gymnosperms. A cycadeoid is attacked by a hungry triceratops, and the versatile grasses squat the
    property before the beleaguered gymnosperm has a chance to leave descendants. Soon the cycadeoids are all gone.
    The Triceratopses are gone. And the T-Rexes are gone. What remains behind are the members of the new order: the
    angiosperms and the tiny animals that have carved a niche in this expanding jungle and who are unaffected by what is
    going on in the world of giants above. The incoming species are slated to be the rulers of the Cenozoic. This sequence
    faithfully reflects the record. An impact winter would have instantly devastated all species in the same proportion, and
    this is not at all what we observe.
When a broad category of families comes to an
end, the animals that developed a relation with
them for thousands of years cannot suddenly
change their diets at the last moment.
Unfortunately for them, they have had ample
time to  acquire immunities to common
diseases and begin to multiply. As the herds
expand in both numbers and size (Cope's Law),
the lush forests and beds contract. At some
critical point we have the many chasing the few
and the entire system collapses quite suddenly.
This phenomenon occurs in the seas as well.
The primary oceanic production consists of
phytoplankton. All aquatic animals ultimately
owe their livelihood to these plants.