Biology Reference
In-Depth Information
1.00
P P
M M
N
N
V
V
LL
L
M
N
P
V
N
P
M
V
L
P
V
M
N
N
N
N
N
N N
N
N
N
N N
N
N
N
N N
M
M
M
M
M
M M
M
M
M
M
M M
M
M
M
P
V
V
V
V
V V
V
V
V
V
V
V V
V
V V
L
P
P
P
P
P
P P
P
P
P
P
P P P
P
L
L
L
L
0.85
L
L
L
L
L
L
L
L
L
L
L
L
0.70
0.55
v
n
n
l
p
p
l
v
n
v
p
l
v
p
v
n
l
p
nn
n
v
p
vv
v
p
nnn
p
p
v
nnn
v
l
p
p
v
vv
vvv
n
ppp
n
nn
n
l
p
p
p
v
v
nn
n
p
pp
p
v
v
l
l
l
l
l
l
l
l
l
l
0.40
l
l
l
l
l
0
7
14
21
GENERATION
Fig. 8.14
Change in mean observed heterozygosity across generations for the populations
discussed in
Fig. 8.13.
Lowercase trials have source populations with 10 loci, each locus with
2 unique alleles of equal frequency, while uppercase letters have 30 loci each with 100 unique
alleles of equal frequency. Except when the founders are placed exactly at the lower left corner
of the preserve (letters L and l), changes in heterozygosity across generations do not differ
(p > 0.05) for populations placed at different distances from the lower left corner, even if the
borders recede from the founders by only 5 grid units (letter M among the uppermost data
points). X and Y coordinate recession distance of the preserve lower left corner from point
0,0 was 0 grid units for L and l, 5 units for M, 10 units for N and n, 40 units for P and p, and
2,560 units for V and v.
placing the founders much more deeply into the preserve is not necessarily
more effective in avoiding increases in homozygosity than situating them
only a short distance into the preserve (a less costly enterprise).
Under the given input conditions, F for the populations with growth as
depicted in Fig. 8.13 increases as distance of the founders from the lower left
preserve corner increases (
Fig. 8.15).
Note that trials using the same letter are
rather similar in value regardless of the allelic panel. At generation 20, two
“curve trajectories” are apparent. The lower curve includes trials with the
distance of founders from the preserve corner as follows: L and l, 0 grid units;
M, 5 units; and N or n, 10 units. The higher curves include the following: P
and p, 40 units; and V and v, 2,560 units. This pattern, where F (a measure
of inbreeding) is less for populations initiated with founders closer to the
lower left border (Fig. 8.15), is a pattern ascribed earlier to the potential
for greater spatial separation of offspring when the founders are placed at
greater distances from a border (e.g., see discussion of
Fig. 8.6
).
Thus, while
loss of observed heterozygosity is faster for populations founded near the
preserve corner, inbreeding is greater in populations established at greater
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