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On the trail of strategic growth patterns of N. pulcher. Or: Why don‘t they grow?. Introduction - N. pulcher - About growth - Questions Queue - Predictions - Set up - Results - Conclusions Relatedness - Predictions - Set up Further Discussion….
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On the trail of strategic growth patterns of N. pulcher Or: Why don‘t they grow?
Introduction - N. pulcher - About growth - Questions Queue - Predictions - Set up - Results - Conclusions Relatedness - Predictions - Set up Further Discussion… groups consist of a mixture between related and unrelated individuals. sexes don‘t change and are monomorphic group structure is hierarchic mostly according to size of the individuals size increase from one individual to the next is usually the body length of the smaller individual x 1.3 breeders sometimes also one breeding male and two breeding females in the same territory (field) helpers that defend territory (large) helpers that care for the brood (small, rarer also large) fry N. pulcher group structure
Introduction - N. pulcher - About growth - Questions Queue - Predictions - Set up - Results - Conclusions Relatedness - Predictions - Set up Further Discussion… ... whenever a hierarchically structured group shares a common habitat it‘s a source for competition and conflict. Control! Examples for such conflicting growth patterns are: strategic growth, gonadal growth, group size effects on growth The thing with growth is...
Introduction - N. pulcher - About growth - Questions Queue - Predictions - Set up - Results - Conclusions Relatedness - Predictions - Set up Further Discussion… Is defined as: a restricted growth within a socially structured (mostly hierarchic) group, because of control by dominant individuals. a restricted growth because of ecological constraints. it can either be influenced by any dominant (dominance effect) only by dominats of the same sex as the affected subordinate (queue effect) Strategic Growth
Introduction - N. pulcher - About growth - Questions Queue - Predictions - Set up - Results - Conclusions Relatedness - Predictions - Set up Further Discussion… Is there strategic growth in N. Pulcher? If so, is there the same restriction for small and large helpers? Is there the same restriction for female and male helpers? What changes are there if the sex ratio of the helpers changes in a group? Questions
Introduction - N. pulcher - About growth - Questions Queue - Predictions - Set up - Results - Conclusions Relatedness - Predictions - Set up Further Discussion… Breeders tolerate a helper more readily when it is small (minimal size difference). Predictions
Introduction - N. pulcher - About growth - Questions Queue - Predictions - Set up - Results - Conclusions Relatedness - Predictions - Set up Further Discussion… The larger a helper gets the more likely it is able to: sneak spawn (as soon as it becomes fertile) Predictions
Introduction - N. pulcher - About growth - Questions Queue - Predictions - Set up - Results - Conclusions Relatedness - Predictions - Set up Further Discussion… The larger a helper gets the more likely it is able to: take over the territory Predictions
Introduction - N. pulcher - About growth - Questions Queue - Predictions - Set up - Results - Conclusions Relatedness - Predictions - Set up Further Discussion… The larger a helper gets the more likely it is able to: take over the territory Predictions
Introduction - N. pulcher - About growth - Questions Queue - Predictions - Set up - Results - Conclusions Relatedness - Predictions - Set up Further Discussion… The larger a helper gets the more likely it is able to: disperse Predictions
Introduction - N. pulcher - About growth - Questions Queue - Predictions - Set up - Results - Conclusions Relatedness - Predictions - Set up Further Discussion… Also relatedness and as such the indirect fitness benefits of staying in a group should decrease with size. This is not important for our experiment – our groups are artificial. Predictions
Introduction - N. pulcher - About growth - Questions Queue - Predictions - Set up - Results - Conclusions Relatedness - Predictions - Set up Further Discussion… Large Helpers: pose a greater risk to breeders in general should have more restricted growth than small ones large male helpers should be more restricted in growth sneak spawn more easily than females are more likely to take over territories since there is only one dominant male per territory should be less restricted in growth because the size distance to the male breeder and potential competitor is larger than to the female breeder Females may lay larger clutches as appeasements to make the large helper stay male helpers disperse more Large Helpers
Introduction - N. pulcher - About growth - Questions Queue - Predictions - Set up - Results - Conclusions Relatedness - Predictions - Set up Further Discussion… large female helpers should show more restricted growth the size distance to the female breeder and potential competitor is less large than to the female breeder should show less restricted growth since they cannot participate in sneak spawning as well as males tolerated as secondary females in the territory Female helpers disperse less Large Helpers
Introduction - N. pulcher - About growth - Questions Queue - Predictions - Set up - Results - Conclusions Relatedness - Predictions - Set up Further Discussion… Large Helpers
Introduction - N. pulcher - About growth - Questions Queue - Predictions - Set up - Results - Conclusions Relatedness - Predictions - Set up Further Discussion… Small Helpers: do not pose such a great risk as large helpers should not show as great a growth restriction also there should not be a great difference between females and males since the conflict with the breeders isn‘t as pronounced selfish reproduction isn‘t as important with a smaller size Small Helpers
Introduction - N. pulcher - About growth - Questions Queue - Predictions - Set up - Results - Conclusions Relatedness - Predictions - Set up Further Discussion… Set Up
Introduction - N. pulcher - About growth - Questions Queue - Predictions - Set up - Results - Conclusions Relatedness - Predictions - Set up Further Discussion… Set Up
Introduction - N. pulcher - About growth - Questions Queue - Predictions - Set up - Results - Conclusions Relatedness - Predictions - Set up Further Discussion… Measured: standard length, total length DNA probes by fin clipping body mass What we observed and measured:
Introduction - N. pulcher - About growth - Questions Queue - Predictions - Set up - Results - Conclusions Relatedness - Predictions - Set up Further Discussion… Observed: spawning (opportunistically) interaction (3 to 5 days later) "who is where and when" brood care (on the same day) brood care (much later) What we observed and measured:
Introduction - N. pulcher - About growth - Questions Queue - Predictions - Set up - Results - Conclusions Relatedness - Predictions - Set up Further Discussion… Growth: overview
Introduction - N. pulcher - About growth - Questions Queue - Predictions - Set up - Results - Conclusions Relatedness - Predictions - Set up Further Discussion… Blumberg: small helpers N = 48 males females N = 21 N = 27
Introduction - N. pulcher - About growth - Questions Queue - Predictions - Set up - Results - Conclusions Relatedness - Predictions - Set up Further Discussion… Blumberg: large helpers N = 48 males females N = 24 N = 24
Introduction - N. pulcher - About growth - Questions Queue - Predictions - Set up - Results - Conclusions Relatedness - Predictions - Set up Further Discussion… Small Helpers no matter what the initial size, they always grow the same. no difference between males and females There seems to be restriction when initial size is small! Large helpers: males seem to grow more when the initial size is larger competition? females show pretty much normal growth Conclusions: Blumberg
Introduction - N. pulcher - About growth - Questions Queue - Predictions - Set up - Results - Conclusions Relatedness - Predictions - Set up Further Discussion… In theory...
Introduction - N. pulcher - About growth - Questions Queue - Predictions - Set up - Results - Conclusions Relatedness - Predictions - Set up Further Discussion… In theory... Queue
Introduction - N. pulcher - About growth - Questions Queue - Predictions - Set up - Results - Conclusions Relatedness - Predictions - Set up Further Discussion… In theory... Dominance
Introduction - N. pulcher - About growth - Questions Queue - Predictions - Set up - Results - Conclusions Relatedness - Predictions - Set up Further Discussion… In theory... Queue and Dominance
Introduction - N. pulcher - About growth - Questions Queue - Predictions - Set up - Results - Conclusions Relatedness - Predictions - Set up Further Discussion… Queue or Dominance? between sh and lh N(m) = 21 N(f) = 27 between sh and bf between sh and bm N(m) = 21 N(f) = 27 N(m) = 21 N(f) = 27
Introduction - N. pulcher - About growth - Questions Queue - Predictions - Set up - Results - Conclusions Relatedness - Predictions - Set up Further Discussion… Queue or Dominance? between sh and lh
Introduction - N. pulcher - About growth - Questions Queue - Predictions - Set up - Results - Conclusions Relatedness - Predictions - Set up Further Discussion… Queue or Dominance? between sh and lh
Introduction - N. pulcher - About growth - Questions Queue - Predictions - Set up - Results - Conclusions Relatedness - Predictions - Set up Further Discussion… Queue or Dominance? between lh and bf between lh and bm N(m) = 24 N(f) = 24 N(m) = 24 N(f) = 24
Introduction - N. pulcher - About growth - Questions Queue - Predictions - Set up - Results - Conclusions Relatedness - Predictions - Set up Further Discussion… Small Helpers With the large helpers the situation is unclear (another strange competition effect?) the females seem to be the main cause with the breeders more or less the dominance situation Large helpers: again the females are showing this strange pattern... helper females are a problem for the breeder female when they are small easily controlled when bigger then no control (because of intervention of breeder males?) Conclusions
Introduction - N. pulcher - About growth - Questions Queue - Predictions - Set up - Results - Conclusions Relatedness - Predictions - Set up Further Discussion… Egg Cleaning and Fanning
Introduction - N. pulcher - About growth - Questions Queue - Predictions - Set up - Results - Conclusions Relatedness - Predictions - Set up Further Discussion… Sneak spawning was opportunistically done. There was sneak spawning by both large and small helper males. Male sneak spawning occurred more often (Very often in fact!). Usually large helpers would do more sneak spawning than the smaller ones. So actually all is as predicted – except for large proportion of sneak spawning. Spawning
Introduction - N. pulcher - About growth - Questions Queue - Predictions - Set up - Results - Conclusions Relatedness - Predictions - Set up Further Discussion… Is N. pulcher able to assess relatedness? How great is the acceptance of related helpers compared to unrelated helpers of different sizes? Do fish grow more or less when they are related to the breeders? How great is the participation of brood care of a helper within a group when it’s related or not? Questions
Introduction - N. pulcher - About growth - Questions Queue - Predictions - Set up - Results - Conclusions Relatedness - Predictions - Set up Further Discussion… Acceptance: When breeders assess relatedness, related helpers are more readily accepted. related helpers also grow more Brood care: Unrelated : there is more when "pay-to-stay“ is important Related: there is more when indrect fitness benefits etc. are important General idea of this experiment: Is it really relatedness that‘s important or is it rather more recognition that will play a role? Predictions
Introduction - N. pulcher - About growth - Questions Queue - Predictions - Set up - Results - Conclusions Relatedness - Predictions - Set up Further Discussion… Rearing young
Introduction - N. pulcher - About growth - Questions Queue - Predictions - Set up - Results - Conclusions Relatedness - Predictions - Set up Further Discussion… Set up
Introduction - N. pulcher - About growth - Questions Queue - Predictions - Set up - Results - Conclusions Relatedness - Predictions - Set up Further Discussion… Set up
Introduction - N. pulcher - About growth - Questions Queue - Predictions - Set up - Results - Conclusions Relatedness - Predictions - Set up Further Discussion… What I observed and measured: Measured: • standard length, total length • DNA probes by fin clipping • body mass
Introduction - N. pulcher - About growth - Questions Queue - Predictions - Set up - Results - Conclusions Relatedness - Predictions - Set up Further Discussion… Set up Observed: 3rd day after putting the breeders in • interaction • "who is where and when" 1 day after brood laying • brood care • interaction • "who is where and when" 3 days after brood laying • interaction • "who is where and when"
Introduction - N. pulcher - About growth - Questions Queue - Predictions - Set up - Results - Conclusions Relatedness - Predictions - Set up Further Discussion… The experiment is not yet finished. No results are quantified yet! Results
Introduction - N. pulcher - About growth - Questions Queue - Predictions - Set up - Results - Conclusions Relatedness - Predictions - Set up Further Discussion… Feel free to ask questions! Further discussion...