experimental

1
experimental
Yeast? Egg removal? Ne?
Monogamy
Virgins
1 M 1 F
Initially 5 Fem. per treatment thereafter 1/30
of each treatment
Starting Population LHM-nub
nubbin (nb/nb)
15 F
20 M
2 x 96 straws in pipette tip holder
10 vials
10 vials
Protection
5 M 50 F
5 F 5 F 5 F
red-eye F (bw)
Juvenile ? adult development
20 M 15 F
15 F
20 M
Starting Population LHM-bw LHM
4, 2 liter cages
30 vials
brown-eye F (bw/bw)
Sexual selection
20 vials
20 vials
20 vials
50 M 50 F
4, 2 liter cages
Count all phenotypes
control
Virgins
Monogamy
1 M 1 F
Starting Population LHM-nub
15 F
20 M
nubbin (nb/nb)
2 x 96 straws in pipette tip holder
10 vials
10 vials
Sexual selection
x F y F z F
20 M 15 F
15 F
20 M
50 M 50 F
red brown
Starting Population LHM-bw LHM
Juvenile ? adult development
10 vials
10 vials
10 vials
4, 2 liter cages
10 vials
Virgin collection
Initial mating (2h)
Interaction (2 days)
Oviposition (18h)
2
experimental
Monogamy
Virgins
1 M 1 F
Initially 5 Fem. per treatment thereafter 1/30
of each treatment
Starting Population LHM-nub
nubbin (nb/nb)
15 F
20 M
2 x 96 straws in pipette tip holder
14 vials
14 vials
Protection
5 M 48 F
3 F 3 F 3 F
red-eye F (bw)
Juvenile ? adult development
20 M 15 F
15 F
20 M
Starting Population LHM-bw LHM
4, 2 liter cages
64 vials
brown-eye F (bw/bw)
Sexual selection
27 vials
27 vials
27 vials
48 M 48 F
4, 2 liter cages
Count all phenotypes
Virgin collection
Initial mating (2h)
Interaction (2 days)
Oviposition (18h)
Yeast? Egg removal? Ne? Fems collected day 9,
males day 11. Bias with monogamy? Collect over
9-11?
3
version 2, part 1 (Repeat Rice lab 05)
Experimental
Protection
5 M 50 F
5 F 5 F
red-eye F (bw)
Juvenile ? adult development
20 M 15 F
15 F
20 M
Starting Population LHM-bw
3, 2 liter cages
30 vials
brown-eye F (bw)
Sexual selection
20 vials
20 vials
20 vials
50 M 50 F
3, 2 liter cages
control
Initially 5 Fem. per treatment thereafter 1/30
of each treatment
Sexual selection
5 F 5 F
20 M 15 F
15 F
20 M
50 M 50 F
red brown
Starting Population LHM-bw
Juvenile ? adult development
10 vials
10 vials
10 vials
3, 2 liter cages
15 vials
Virgin collection
Initial mating (2h)
Interaction (2 days)
Oviposition (18h)
4
Experimental
version 2, part 2, (Brett addition sympatric
populations during development
Monogamy
Virgins
1 M 1 F
Initially 5 Fem. per treatment thereafter 1/30
of each treatment
brown-eye F (bw)
15 F
20 M
96 straws
Starting Population LHM-bw
10 vials
10 vials
5 F 5 F
Juvenile ? adult development
20 M 15 F
15 F
20 M
30 vials
red-eye F (bw)
Sexual selection
10 vials
10 vials
10 vials
50 M 50 F
3, 2 liter cages
5
Monogamy allele (bw/bw) V. SS in population
cages. Possible 2nd variable duration of male
female interaction (1 day, 3 days) OR Third
treatment lower sex ratio (as Rice) to produce a
protected environment. 51, femalemale
6

• Monogamous Drosophila populations have higher Ro.
  So why doesnt monogamy evolve in Drosophila, or
  any species?
• H1 Individual selection favors nonmonogamy
• H2 Fitness landscape prevents the monogamy peak
  from being reached.
• Life history high density populations make
  sexual selection strong.
• Test between H1 and H2 above. Introduce monogamy
  allele into promiscuous populations.
• The monogamy allele (bw) is expressed in both
  sexes.
• Introduce it as in Morrow et al, 05, except using
  
• Strict genetic monogamy
• bw individuals are randomly assigned mates
  (bw/bw or bw) for one day. Then bw/bw
  individuals enter a population cage and bw
  individuals are held in single sex vials until
  egg laying.
• See next slide for visual description

7
why doesnt monogamy evolve individual selection
or unattainable fitness peak?
Generation 1
This is protection from males, not a realistic
form of monogamy
Monogamy
Virgins
7 M
Discard
M Male F Female Red bw Black bw
1 red 1 red or brown,
7 F
Mix all adults. Red adults get monogamy vial and
random mate (either eye color)
24h
24h
Starting Population LHM and LHM-bw
7 M 7 F
7 F 93 F
7 M 93 M
1 F 9 F
Juvenile ? adult development
Sexual selection
10 vials
brown-eye (bw/bw)
20F 20 M
48h
Each egg laying vial contains only females. Red
females equally distributed among the vials.
Brown females
8
Are males sexual parasites?

• Sexual recombination imposes a direct cost to
  populations each individual can only pass on
  one-half of their genes to their offspring. Yet
  the advantages of recombination were so great
  that it persisted and has been maintained in the
  vast majority of macroscopic species.
• The vast majority of sexually reproducing species
  are also sexually dimorphic. The rarity of
  isomorphic sexes implies that it is unstable. The
  ubiquity and pattern of sexual dimorphism reveals
  that one sex specializes in parenting while the
  other specializes in fertilization (hereafter
  referred to as females and males for brevity).
  This creates a second general cost of sex (males)
  
• Sexual dimorphism is absent or minimal at the
  beginning of development and increases
  dramatically as individuals prepare for mating
  and fertilization, reaching its zenith at the
  gamete stage in reproductive tissues (Parisi et
  al. 2003). Less is known about how the global
  patterns of sex-biased gene expression change
  throughout life and between different
  developmental stages9. Most of the phenotypic
  differences seen between sexes occur after sexual
  differentiation and arise by a combination of the
  effects of genetic and hormonal factors.
  Ellengren MS
• By sexual maturity adults of opposite sex are
  often phenotypically less similar than those of
  the same sex in another species, leading
  sometimes to misidentification of males and
  females into separate species.
• Gametes are sexually dimorphic to such an extent
  that morphological similarity is generally
  greater within sexes across distantly related
  phyla than between sexes within species (e.g.,
  sperm swim and eggs are much larger and
  energetically rich targets).
• The above pattern implies that sexual dimorphism
  is essentially the manifestation of sexual
  selection.
• The above begs the question, is the cost of males
  (to the population) recouped, or, are males
  sexual parasites (of females)?
• The benefits or costs of males hinge on sexual
  selection. Either it acts as a filter, selecting
  males with greater heritable quality that
  promotes the survival of populations or it is a
  load on populations that reduces their viability.
• Citations
• From Ellegren review (nature genetics). For
  example, when whole adult females and males of
  Drosophila melanogaster are compared, up to 57
  of the genes exhibit sex-biased expression6. The
  vast majority of these differences can be
  attributed to genes expressed in reproductive
  tissues when reproductive tissues are excluded,
  the fraction of sex-biased genes may be as low as
  1-2 (Ref. 7)Parisi, M. et al. Paucity of genes
  on the D. melanogaster X chromosome showing male
  biased expression. Science 299, 697700 (2003).

9
Are males sexual parasites?
Experiment compete monogamous female against ss
females. Allopatric during mating but sympatric
otherwise. ½ females from each group in each
vial, with egg laying and larval competition.
Experiment one direct and evolved effects both
included let natural selection take its course.
The number of breeding females (total) remains
the same but the fraction from each population is
based on the total offspring production last
generation. This means that even if there is no
evolution occurring, but monogamy induces higher
fecundity, the monogamy population will go to
fixation. The change should accelerate as the
low Ne results in differential inbreeding in the
smaller population which will reinforce the drive
toward extinction (extinction vortex, sule and
Mills). Experiment two maintain the populations
at 50 of each type of female regardless of the
fraction of offpsring produced. Any change
overtime in the fraction of each population
represents direct and evolutionary effects as one
group adapts to the other. This could also result
in an accelerating curve due to adaptation and
direct effects. The later exists from gen 1, but
the later will increase over time.
1 .5 0
Exp 1
Exp 2
10
Are males sexual parasites?
Experiment compete monogamous female against ss
females. Allopatric during mating but sympatric
otherwise. 8/7/07 Hi Bill, I am planning an
experiment. There will be two treatments
Monogamy (1 male 1 female) and Promiscuity (11
sex ratio in small cages).  Monogamy bw/bw
Promiscuous /.  The populations are allopatric
during mating but sympatric during female and
offspring competition (after 2 days of mating the
males will be discarded and the M and P females
housed together, 11 in vials for 24 hours of egg
laying). The offspring will all be counted to
measure the fitness of each population, each
generation. The experiment will continue until
one population is driven toward extinction (let's
say 50 of its original size -- to be determined
later).  Problem As one population is selected
against, decreased N results in differential
inbreeding that accelerates its movement toward
extinction. Solution  I am planning to keep the
adult census size of every population identical
throughout the experiment and use arithmatic to
calculate the actual fitness of each population
based on the cumulative fitness data. For
example Generation 1 1000 offspring in M1
(monogamy replicate 1) 980 offspring in P1
(promiscuity replicate 1) Generation 2 1000
offspring in M1 980 offspring in P1 After two
generations, the calculated fitness of P1
(980/1000) (980/1000) 0.98 0.98 0.9604 At
this rate, after G25, P1 fitness 0.603   Is
this solution reasonable?   The other Ne related
problem is that sexual selection causes decreased
Ne. I think it is appropriate to include this
source of Ne bias between treatments b/c it is an
inevitable result of sexual selection.   Thanks
for your thoughts.   Brett  
11
Evolution of female resistance via environmental
choice
Fly entry port
Courtship inhibiting light
Control light
Light opaque cages (---) and connecting tubes
(----) that conduct light to middle cage
Each generation, WT adults are dumped through the
entry port into the middle cage (illuminated from
both ends by connecting tubes from each food
cage). The control and experimental light sources
are positioned at the end of their respective
cages and are the only sources of light entering
into the 3 room condo. Males and Females assort
into either food cage for reproduction.
Prediction females will evolve preference for
inhabiting and egg laying in the courtship
inhibiting cage. Separate control experiments, to
demonstrate the benefits of the courtship
inhibiting light to females. Using food chambers,
above Place standard number of males and females
in each and measure courtship and fecundity
rates.