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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.