biblio-excerptise:   a book unexamined is not worth having

Hen's Teeth and Horse's Toes

Stephen Jay Gould

Gould, Stephen Jay;

Hen's Teeth and Horse's Toes

Norton, 1983, 413 pages

ISBN 0393017168, 9780393017168

topics: |  biology | evolution | paleontology | genetics | sociology | postmodern


It is Gould's ability to draw linkages across immense chasms that makes his
writing so unputdownable.  In the second essay, for instance (Non-Moral
nature), he starts with a quotation on how Christiandom attempted to defend
God's benevolence given nature's violent ways, followed by a deep discussion
on the nasty (from a human pov) habits of parasites that eat
their hosts while keeping them alive, discussing en route the English penalty
of "drawing and quartering", and going onto the intensely anthropomorphic
descriptions of the process, from the French naturalist JH Fabre.  He finally
returns to arguments for God's benevolence, showing how Britain's leading
etymologist Rev. Kirby, gave an anthropomorphic slant to the process,
downplaying the cruelty.  The essay closes with an attack on "secular
humanism" - which is proposed by creationists as the religion of the
evolutionists.

Writing essays of such quality one every month is an amazing exercise in
genius.  Dawkins reviews several of his books, including this one, in the
Devil's Chaplain, (p. 199}: When you have to turn these pieces out once a
month you must pick up some of the habits of the professional working to a
deadline - this is not a criticism - Mozart did the same.  Gould's writing
has something of the predictability we enjoy in Mozart, or in a good meal.
His essays are to a recipe: One part biological history, one part biological
politics, and one part vignettes of biological wonder.  The essays themselves
seem to follow a formula or menu.  As appetizer there is the quotation from
light opera or the classics, ... [followed by] the conspicuous erudition of
the main course - fluency in several languages, the almost Medawarian
familiarity with literature and humanities...  - AM

QUOTES:

Non-Moral Nature, chapter 2

[the problem of evil and the parasitic ichneumon wasp]
If God is benevolent and the creation displays his "power, wisdom and
goodness," then why are we surrounded with pain, suffering, and apparently
senseless cruelty in the animal world?
Geologist William Buckland, and later a dean at Westminster, had this
justification:

    The appointment of death by the agency of carnivora as the ordinary
    termination of animal existence, appears therefore in its main results to
    be a dispensation of benevolence; it deducts much from the aggregate
    amount of the pain of universal death; it abridges, and almost
    annihilates, throughout the brute creation, the misery of disease, and
    accidental injuries, and lingering decay; and impose such salutary
    restraint upon excessive increase of numbers, that the supply of food
    maintains perpetually a due ratio to the demand. The result is, that the
    surface of the land and depths of the waters are ever crowded with
    myriads of animated beings, the pleasures of whose life are coextensive
    with its duration; and which throughout the little day of existence that
    is allotted to them, fulfill with joy the functions for which they were
    created.
[But the grossest challenge to God's benevolence comes not from mere predation
but from internal ingestion by parasites.  ]

Parasitologists speak of ectoparasitism when the uninvited guest lives on the
surface of its host, and endoparasitism when the parasite dwells
within. Among endoparasitic ichneumons, adult females pierce the host with
their ovipositor and deposit eggs within. (The ovipositor, a thin tube
extending backward from the wasp's rear end, may be many times as long as the
body itself.) Usually, the host is not otherwise inconvenienced for the
moment, at least until the eggs hatch and the ichneumon larvae begin their
grim work of interior excavation.

Among ectoparasites, however, many females lay their eggs directly upon the
host's body. Since an active host would easily dislodge the egg, the
ichneumon mother often simultaneously injects a toxin that paralyzes the
caterpillar or other victim. The paralyzes may be permanent, and the
caterpillar lies, alive but immobile, with the agent of its future
destruction secure on its belly. The egg hatches, the helpless caterpillar
twitches, the wasp larvae pierces and begins its grisly feast.

Since a dead and decaying caterpillar will do the wasp larvae no good, it
eats in a pattern that cannot help but recall, in our inappropriate
anthropocentric interpretation, the ancient English penalty for treason —
drawing and quartering, with its explicit object of extracting as much
torment as possible by keeping the victim alive and sentient. As the king's
executioner drew out and burned his client's entrails, so does the ichneumon
larvae eat fat bodies and digestive organs first, keeping the caterpillar
alive by preserving intact the essential heart and central nervous
system. Finally, the larvae completes its work and kills its victim, leaving
behind the caterpillar's empty shell. Is it any wonder that ichneumons, not
snakes or lions, stood as the paramount challenge to God's benevolence during
the heyday of natural theology?

J. H. Fabre, the great nineteenth-century French entomologist, who remains to
this day the preeminently literate natural historian of insects, made a
special study of parasitic wasps and wrote with an unabashed anthropocentrism
about the struggles of paralyzed victims (see his books Insect Life and The
Wonders of Instinct). He describes some imperfectly paralyzed caterpillars
that struggle so violently every time a parasite approaches that the wasp
larvae must feed with unusual caution. They attach themselves to a silken
strand from the roof of their burrow and descend upon a safe and exposed part
of the caterpillar:

    The grub is at dinner: head downwards, it is digging into the limp belly
    of one of the caterpillars. . . . At the least sign of danger in the heap
    of caterpillars, the larva retreats . . . and climbs back to the ceiling,
    where the swarming rabble cannot reach it. When peace is restored, it
    slides down [its silken cord] and returns to table, with its head over
    the viands and its rear upturned and ready to withdraw in case of need.

In another chapter, he describes the fate of a paralyzed cricket:

    One may see the cricket, bitten to the quick, vainly move its antennae
    and abdominal styles, open and close its empty jaws, and even move a
    foot, but the larva is safe and searches its vitals with impunity. What
    an awful nightmare for the paralyzed cricket!

Some wasps must battle with other parasites over a host's body. Rhyssella
curvipes can detect the larvae of wood wasps deep within alder wood and drill
down to a potential victim with its sharply ridged ovipositor. Pseudorhyssa
alpestris, a related parasite, cannot drill directly into wood since its
slender ovipositor bears only rudimentary cutting ridges. It locates the
holes made by Rhyssella, inserts its ovipositor, and lays an egg on the host
(already conveniently paralyzed by Rhyssella), right next to the egg
deposited by its relative. The two eggs hatch at about the same time, but the
larva of Pseudorhyssa has a bigger head bearing much larger
mandibles. Pseudorhyssa seizes the smaller Rhyssella larva, destroys it, and
proceeds to feast upon a banquet already well prepared.

The Reverend William Kirby, rector of Barham, and Britain's foremost
entomologist, chose to ignore the plight of caterpillars and focused instead
upon the virtue of mother love displayed by wasps in provisioning their young
with such care.

    The great object of the female is to discover a proper nidus for her
    eggs. In search of this she is in constant motion. Is the caterpillar of
    a butterfly or moth the appropriate food for her young? You see her
    alight upon the plants where they are most usually to be met with, run
    quickly over them, carefully examining every leaf, and, having found the
    unfortunate object of her search, insert her sting into its flesh, and
    there deposit an egg. . . . The active Ichneumon braves every danger, and
    does not desist until her courage and address have insured subsistence
    for one of her future progeny.

Kirby found this solicitude all the more remarkable because the female wasp
will never see her child and enjoy the pleasures of parenthood. Yet her love
compels her to danger nonetheless:

    A very large proportion of them are doomed to die before their young come
    into existence. But in these the passion is not extinguished. . . . When
    you witness the solicitude with which they provide for the security and
    sustenance of their future young, you can scarcely deny to them love for
    a progeny they are never destined to behold.

It took Darwin himself to derail this ancient tradition — and he proceeded in
the gentle way so characteristic of his radical intellectual approach to
nearly everything. The ichneumons also troubled Darwin greatly and he wrote
of them to Asa Gray in 1860:

    I own that I cannot see as plainly as others do, and as I should wish to
    do, evidence of design and beneficence on all sides of us. There seems to
    me too much misery in the world. I cannot persuade myself that a
    beneficent and omnipotent God would have designedly created the
    Ichneumonidae with the express intention of their feeding within the
    living bodies of Caterpillars, or that a cat should play with mice.

Indeed, he had written with more passion to Joseph Hooker in 1856: "What a
book a devil's chaplain might write on the clumsy, wasteful, blundering, low,
and horribly cruel works of nature!"

Revisits the creationism attack over three essays towards the end of the
book.


amitabha mukerjee (mukerjee [at] gmail.com) 17 Feb 2009