Actual Data versus NEWGARDEN: American Chestnut - Genetic Diversity in Establishing Plant Populations: Founder Number and Geometry - page 261

of the trials exhibited a pronounced difference in F value compared to the
other trials, all beginning with an excess of heterozygotes (F = approximately
-0.07), and climbing to 0.00 to 0.03 after 100 rounds of mating (data not
shown), at which point all F value trial curves cease to increase further. These
results refl ect what actual chestnut data from West Salem demonstrated:
even with small numbers of founders, inbreeding driven by excess mating of
related individuals, localized subdivision, and/or drift does not seem to be
occurring in these chestnut-like virtual populations. This conclusion applies
even to the very slow-growing population e. NEWGARDEN results for these
trials concerning the retention of unique alleles at the population level are
not very informative since all living individuals are tallied, including all of
the founders. Thus, at the population level, no unique alleles are lost (data
not shown). The suite of unique alleles present in each separate new cohort
tells a slightly different story, as will be explained below.

0.94

A

a b e f

0.93

e
ee e eeee e ee eeeee ee ee e
e

ff f f ffff f ff f f ffff f fff ffffff ffff fff fffffffffffffffffff f ff ffffffffffffffffffffffffffffffffff ffffff

bbb bb bbbb bb bbbbbbb bbbbb b b bbbbbbbbbb bbbbbbbbbbbbbbb bbbbbbbbbbbbbbb bbbbbbbbbbbbbbbbbbbb bbbbbbbbbbbbbbb

aaa a aaaaaaaaaaaaaaa aaaaaa a aaa aaaaaaaaaaaaaaaaaaaaaaaaa aaaaaaaaaaaaaaaaaa aaaaaaaaaaaaaaaaaaaaaaaaa

a aa

f ff f

0.92

eeeeee

eee eeee eeeee eeeeeeeeeeeeeeeee eeeeeeeeeeeeeeeeeeeeeeee eeeeeeeeeeeeeeeee
ee

0.91

0 20 40 60 80 100

0.1

f ff f f f f f f f f f f f ff f f f f f f f fff f ff f ff f f ff ff f ffffffff ffff fffffffffffffff fffffffffffffffff f fff f ffffffffffff

a a aa aa a a a a a a aa a a a a a a a a aa aaa aa a aa aa a a aaaaaa aaaaaa aaaaaaaaaa a aa aaaaaaaaaaaaaaaaaaa a aa a aa a a aaaa

0.0

b b b bb b bb bb b b bb b b b b bb bb b bb b bb bb bbbbbbb b bbbb bbb b b b b bb b bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb

e e e e e e e e e e e e e e e e ee e e e eee e e ee e e e ee e e e e e e e e e ee ee e e e e ee e e eeeee

f a e b

b b b b bb b b b

-0.1

bb

e e e

a a a a a a
a

a

e e e e
e

e
e

e
e e
e e

-0.2

e
e e e

e

e

e

-0.3

e

e e
e

e

-0.4

e e
e

e

B

e
e e e e e

-0.5

e
e e

e

-0.6

0 20 40 60 80 100

GENERATION

Fig. 16.2 Heterozygosity estimated for the entire population (A) and F values for individual
cohorts (B) across generations for NEWGARDEN virtual populations with input conditions
designed to refl ect the development of the West Salem American chestnut population. See
text for details of the basic trial a, and associated trials.