1. LIFE HISTORY STRATEGY (PART 2)

2. Overview – Life History Patterns 1) Fertilization patterns 2) Development patterns 3) Dispersal patterns 4) Settlement patterns 1) Fertilization patterns 2) Development patterns 3) Dispersal patterns 4) Settlement patterns ✓

3. From last lecture Fertilization pattern CostsBenefits External Fertilization-large gamete output -need for synchrony -unpredictable dispersion -gamete dilution -takes advantage of medium Internal Fertilization (no copulation) -large gamete output -unpredictable dispersion -gamete dilution -takes advantage of medium Internal Fertilization (copulation) -energy in mate searching -energy in courtship -less gamete wastage -greater efficiency in reproduction

4. Developmental Patterns -Kinds of eggs Isolecithal Telolecithal yolk 1) Fertilization patterns 2) Development patterns 3) Dispersal patterns 4) Settlement patterns

5. Developmental Patterns -Kinds of eggs Isolecithal Telolecithal Cleavage through entire egg Cleavage not through entire egg 1) Fertilization patterns 2) Development patterns 3) Dispersal patterns 4) Settlement patterns

6. Developmental Patterns -Kinds of eggs Isolecithal Telolecithal Cleavage through entire egg Cleavage not through entire egg Holoblastic Meroblastic 1) Fertilization patterns 2) Development patterns 3) Dispersal patterns 4) Settlement patterns

7. Developmental Patterns -Kinds of eggs Isolecithal - HoloblasticTelolecithal - Meroblastic 1) Fertilization patterns 2) Development patterns 3) Dispersal patterns 4) Settlement patterns

8. Developmental Patterns -Kinds of eggs Isolecithal Telolecithal Holoblastic Meroblastic Planktotrophic larvae Lecithotrophic larvae 1) Fertilization patterns 2) Development patterns 3) Dispersal patterns 4) Settlement patterns

9. Kinds of Development Patterns Free spawning Planktotrophic, free-swimming larvae Settlement and metamorphosis Juvenile Maturation Weakly isolecithal egg Indirect Free spawning Planktotrophic, free-swimming larvae Settlement and metamorphosis Juvenile Maturation Strongly/moderately telolecithal egg Indirect Mating Brooding of embryos Hatch as juvenilesMaturation Strongly telolecithal egg Direct Mating Brooding of embryos Hatch as free- swimming larvae Juvenile Maturation Moderately telolecithal egg Mixed Settlement and metamorphosis 1) Fertilization patterns 2) Development patterns 3) Dispersal patterns 4) Settlement patterns

10. Larval Settlement – Large Scale 1) Fertilization patterns 2) Development patterns 3) Dispersal patterns 4) Settlement patterns 0.2 % recovery 0.18 % recovery 0.2 % recovery Scheltema ‘71

11. Larval Settlement – Large Scale 1) Fertilization patterns 2) Development patterns 3) Dispersal patterns 4) Settlement patterns

12. Scheltema ‘71 Larval Settlement – Large Scale 1) Fertilization patterns 2) Development patterns 3) Dispersal patterns 4) Settlement patterns 10 2 10 4 10 6 10 8 10 10 10 12 10 1210 10 8 10 6 10 4 10 2 Population size Frequency of dispersal

13. Scheltema ‘71 Larval Settlement – Large Scale 1) Fertilization patterns 2) Development patterns 3) Dispersal patterns 4) Settlement patterns North Atlantic Drift Volume of water (m 3 )Total number of larvae North Equatorial Current Equatorial Undercurrent South Equatorial Current 2.45 x 10 5 3.43 x 10 5 2.26 x 10 5 0.98 x 10 5 3.31 x 10 11 4.63 x 10 11 3.05 x 10 11 1.32 x 10 11

14. Point Conception Larval Settlement Large Scale 1) Fertilization patterns 2) Development patterns 3) Dispersal patterns 4) Settlement patterns

15. Point Conception Larval Settlement Large Scale Current Patterns 1) Fertilization patterns 2) Development patterns 3) Dispersal patterns 4) Settlement patterns

16. Point Conception Larval Settlement Large Scale Current Patterns Biogeographical Zones 1) Fertilization patterns 2) Development patterns 3) Dispersal patterns 4) Settlement patterns

17. Embayment Flushing (Gaines & Bertness, ‘92) 1) Fertilization patterns 2) Development patterns 3) Dispersal patterns 4) Settlement patterns

18. Wind & Tidal Currents Associated with internal waves

19. Wind & Tidal Currents Associated with internal waves 1) Fertilization patterns 2) Development patterns 3) Dispersal patterns 4) Settlement patterns

20. Settlement - Behaviour of Larvae Lobster hatches -photopositive- Drifts in plankton (days/weeks) Preference switches to photonegative Lobster settles and undergoes metamorphosis Metamorphosis to postlarva 1) Fertilization patterns 2) Development patterns 3) Dispersal patterns 4) Settlement patterns

21. 3. Benthic/Surface Phenomena Pawlik et al, ‘91. Science 251:421 - settlement of reef-building worm Current Speed -low -medium -high (>15 cm/sec) Phragmatopoma 1) Fertilization patterns 2) Development patterns 3) Dispersal patterns 4) Settlement patterns

22. 3. Benthic/Surface Phenomena Pawlik et al, ‘91. Science 251:421 # settling Current No ‘sampling’Erosion 1) Fertilization patterns 2) Development patterns 3) Dispersal patterns 4) Settlement patterns

23. Early models Larvae in water column Settle randomlyDifferential mortality Adult distribution More recent view Larvae in water column Passive depositionTesting substrate Settle Adult distribution Not settle 1) Fertilization patterns 2) Development patterns 3) Dispersal patterns 4) Settlement patterns

24. Passive Deposition -due to 1) sedimentation rate 2) swimming behaviour 3) bottom flow patterns 1) Fertilization patterns 2) Development patterns 3) Dispersal patterns 4) Settlement patterns

25. Bottom flow patterns Laminar flow 1) Fertilization patterns 2) Development patterns 3) Dispersal patterns 4) Settlement patterns

26. Bottom flow patterns x x x xx Change in angular velocity 1) Fertilization patterns 2) Development patterns 3) Dispersal patterns 4) Settlement patterns

27. Experiment on settling and flow Botman et al 1998 coarse sand rich muds Capitella Mercenaria

28. Experiment on settling and flow Glass beadsMud Flow

29. Experiment on settling and flow Still water Flow MudBeadsMudbeads Capitellayesnoyesno Mercenarianoyes No preference Conclusion - choice is species specific - Mercenaria couldn’t ‘sample’

30. General Model Free swimming larva Alternating photonegative & photopositive behaviour Passive deposition and contact with surface Surface texture Chemical cuesContact with conspecifics Attachment 1) Fertilization patterns 2) Development patterns 3) Dispersal patterns 4) Settlement patterns

31. Larval Settlement 1. Conspecifics 2. Microbial films 3. Prey species 1) Fertilization patterns 2) Development patterns 3) Dispersal patterns 4) Settlement patterns

32. Larval Settlement 1. Conspecifics Free fatty acids Larval settlement Phragmatopoma 1) Fertilization patterns 2) Development patterns 3) Dispersal patterns 4) Settlement patterns

33. Larval Settlement 2. Bacterial films Polysaccharides, Glycoproteins Increased searching or metamorphosis 1) Fertilization patterns 2) Development patterns 3) Dispersal patterns 4) Settlement patterns

34. Larval Settlement 3. Prey species - herbivores Settlement induced by GABA 1) Fertilization patterns 2) Development patterns 3) Dispersal patterns 4) Settlement patterns

35. Larval Settlement 3. Prey species - herbivores Gigartina Porphyra Abalone larva In field -not found on either -not induced to settle on whole fronds 1) Fertilization patterns 2) Development patterns 3) Dispersal patterns 4) Settlement patterns

36. Larval Settlement 3. Prey species - carnivores Onchidoris bilamellata Induces settlement 1) Fertilization patterns 2) Development patterns 3) Dispersal patterns 4) Settlement patterns

37. Larval Settlement 3. Prey species - carnivores Phestilla Induces settlement < 500 Da protein (< 10 mM) 1) Fertilization patterns 2) Development patterns 3) Dispersal patterns 4) Settlement patterns