226 i Flora Unveiled
characteristics of the cultivated tree (from a human perspective) were usually lost in seed-
grown trees, the Greeks interpreted such “degeneration” as a return to the wild state:
[T] hose that ... are planted from slips are all held to breed true. But those that propa-
gate from [seeds] are practically all inferior, and some depart completely from their
kind, as vine, apple, fig, pomegranate and pear; for from the fig seed no cultivated tree
at all is produced, but either a wild fig or fig gone wild ..., and from the noble vine
comes an ignoble one, and often one of a different kind, and sometimes no cultivated
tree at all but a wild one, and occasionally of such a sort that it cannot bring its fruit
to concoction, and some cannot even form fruit but only get as far as flowering. ...
From the stones of the olive grows an olive run wild, and from the berries of the
sweet pomegranate ignoble pomegranates, and from those of the stoneless kind hard
ones, and often sour ones. ... The almond too becomes inferior both in flavor and in
turning from soft to hard.^48Theophrastus believed that the cause of fruit tree degeneration was the inability of the
seed to assimilate the nutrient- rich soils provided in cultivated orchards.
Of course, the correct explanation of fruit tree “degeneration” is that all the cultivated fruit
and nut trees used by the Greeks were hybrids, the end results of multiple crosses between dif-
ferent natural varieties of wild trees. Such crosses had occurred spontaneously in the wild, and
early farmers had selected these wild hybrids for cultivation because of their desirable traits.
The two sets of chromosomes in such hybrid individuals may have come from different vari-
eties, or even from different species, and such hybrids are sometimes sterile. Cultivated fruit
and nut trees are fertile hybrids because they can produce seed, but they cannot breed true
because during sexual reproduction the genes from the two different parental chromosomes
randomly reassort to form new combinations of alleles (alternate versions of genes) on the
chromosomes of the progeny. These new gene combinations give rise to new types of individu-
als. Theophrastus could never have guessed the true biological cause of fruit tree “degenera-
tion” because, having rejected the possibility of sex in plants, the idea that different varieties
of plants could cross with one another was outside his frame of reference. Intentional plant
breeding, which depends on a knowledge of sex in plants, was still centuries away.
Theophrastus died in 288 bce. In accordance with his will, he was buried in a modest cof-
fin in a corner of the botanical garden he loved so well. His funeral was attended by a large
numbers of his former colleagues and pupils, as well as by dignitaries and ordinary citizens.
After his death, the main center of Greek science moved from Athens to Alexandria. The
Alexandrian period of Greek science lasted from about 250 bc to 200 ad, during which time
the emphasis shifted to engineering, mathematics, and astronomy. Galen, from Pergamum
on the Anatolian coast, was the last great Greek biologist of antiquity.
Notes- The earliest evidence for Hebrew inscriptions of proto- biblical texts dates to the tenth cen-
tury bce. See Garfinkel, Y., et al. (2015), The ʾIšbaʿal Inscription from Khirbet Qeiyafa. Bulletin
of the American Schools of Oriental Research 373: 217– 233.
http:// http://www.livescience.com/ 51223- king- david- era- inscription- discovered.html.)