Insects: Dressed for Success

1. Insects:Dressed for Success MTFrazier S.Camazine MTFrazier

2. Insects are the smorgasbord of the animal world!

3. Who Eats Insects?

4. Who Eats Insects? • birds • fish • arthropods (insect and non-insect) • amphibians • mammals • reptiles • humans • even plants!

5. Do insects take this lying down?

6. Insects have an arsenalof defense mechanisms

7. Insects have an arsenalof defense mechanisms • Morphological / Physical • Chemical • Behavioral

8. Insects have an arsenalof defense mechanisms • Morphological / Physical • camouflage (crypsis) • mimicry • mechanical • Chemical • Behavioral

9. Insects have an arsenalof defense mechanisms • Morphological / Physical • camouflage (crypsis) • mimicry • mechanical • Chemical • toxins • venoms • pheromones • Behavioral

10. Insects have an arsenalof defense mechanisms • Morphological / Physical • camouflage (crypsis) • mimicry • mechanical • Chemical • toxins • venoms • pheromones • Behavioral • death feigning • “house” construction

11. 1) Morphological: Camouflage Blend into their background by looking like their background MTFrazier

12. Blend into their background by breaking up their body outline (disruptive coloration) MTFrazier

13. …but it doesn’t work from every angle! MTFrazier

14. Blend into their background by looking like some uneatable part of their background MTFrazier

15. 1) Morphological:Mimicry Aposematism: warning coloration Monarch butterfly = toxic Viceroy butterfly = aposematically "dressed" because it doesn’t have the chemical toxins

16. Looks like a bee, BUT this is actually a fly! Bee-mimic = No venom to back up aposematism

17. Mimicry: • Batesian - the aposematic inedible model (monarch) has an edible mimic (viceroy)- the model suffers, aposematic signal is diluted

18. Mimicry: • Müllerian - both the model and the mimic are distasteful - all benefit from co-existence because predators associate all aposematic color individuals as toxic

19. 1) Morphological: Mechanical Scott Camazine

20. Venoms 2) Chemical: S. Camazine S. Camazine Toxins: sequestered or produced S. Camazine Pheromones

21. Chemically defended insects are typically very apparent to their predators: warning colors S. Camazine S. Camazine

22. Where do insects get their toxins?

23. 3) Behavioral: MTFrazier MTFrazier

24. 3) Behavioral:DIY ‘House Building’ MTFrazier MTFrazier

25. These defense mechanisms often work in combination: Toxins and venoms + aposematic coloration (or sometimes camouflage) Camouflage + behavior Mechanical + chemical

26. In some cases toxins and venoms can be costly for insects to produce S. Camazine MTFrazier Aposematic coloration = primary defense Venoms and toxins = secondary defense

27. MTFrazier Camouflage = primary defense Chemicals = secondary defense

28. It’s not enough to look like a twig (or thorn, stick, etc.) You have to ‘act’ like one to survive! Camouflage + Behavior MTFrazier

29. This caterpillar is even MORE ‘painful’ than it looks S. Camazine mechanical + chemical

30. How did these defenses come about? Evolution Natural Selection By the process of

31. Governing principles of Natural Selection • Populations of species have variability • Variation is maintained by sexual reproduction • Variations can be passed from one generation to the next • Individuals that have variations (traits) that make them better able to survive (adapted) in their environment are more likely to survive and pass on their variation (traits/genes) to the next generation

32. Camouflage in caterpillars First Generation

33. Second Generation

34. ? Third Generation

35. Other factors, in addition to natural selection, influence how species evolve over time: • Mutations • Genetic isolation

36. ReviewInsect Defense Mechanisms: • Morphological / Physical • camouflage (crypsis) • mimicry • mechanical • Chemical • toxins • venoms • pheromones • Behavioral • death feigning • “house” construction