Mimicry in insects (gak).pptx

Mimicry in insects

1. University of agricultural sciences Raichur ENT-504 Insect ecology Mimicry in insects Submitted to: Dr. shivaleela Assistant professor Dept. of entomology presented by: Coa, Raichur gayatri

2. Flow of presentation INTRODUCTION Mimicry and its types Examples of mimicry Case study conclusion

3. Introduction Mimicry is an evolved resemblance between an organism and another object, often an organism of another species. Mimicry may evolve between different species, or between individuals of the same species . Mimicry evolves if a receiver (such as a predator) perceives the similarity between a mimic (the organism that has a resemblance) and a model (the organism it resembles) and as a result changes its behavior in a way that provides a selective advantage to the mimic . The resemblances that evolve in mimicry can be visual, acoustic, chemical, tactile, or electric, or combinations of these sensory modalities . Mimicry may be to the advantage of both organisms that share a resemblance, in which case it is a form of mutualism 2023 Mimicry in insects 3 https://en.Wikipedia.org/wiki/mimicry

4. Mimicry Mimicry is the process by which one species of organism, the mimic, copies the appearance of another species, the model. The mimic may resemble the model in color, shape, size, or behavior. The model is usually not harmful to the mimic, but the mimic may have evolved to look like the model in order to avoid being eaten or attacked. Concept of mimicry was given by Henry Walter Bates in 1862 https://infinitylearn.com/surge/biology/mimicry/

5. Significance of mimicry The main significance of mimicry is to protect the animals against enemies. Mimicry used for self defense which increases the survival value of organisms. 20XX presentation title 5

6. 1)Natural selection: According to Weismann, the natural selection is the only known factor in the production of mimicry. 2) Sharp sudden mutation and its preservation by natural selection. 3) Due to the direct action occurred upon the organism by food, moisture, cold etc. 4) Due to physiological response, such as color sensation. 20XX presentation title 6 Causes of mimicry

7. Batesian mimicry Mullerian mimicry 20XX presentation title 7 Types of mimicry

8. It is form of protective mimicry in which a species that is edible or harmless closely resembles an inedible or harmful species and therefore is avoided by predators. It is named after the English naturalist Henry Walter Bates, after his work on butterflies in the rainforests of Brazil . 2023 Mimicry in insects 8 Batesian mimicry

9. 2023 Mimicry in insects 9 Example.1 T he palatable Dismorphia which mimic toxic Ithomiines . Plate from Henry Walter Bates (1862) illustrating Batesian mimicry between Dismorphia species (top row, third row) and various Ithomiini ( Nymphalidae , second row, bottom row)

10. 2023 Mimicry in insects 10 Example.2 hoverfly and a wasp

11. Müllerian mimicry is a natural phenomenon in which two or more well-defended species(aposematic), often foul-tasting and sharing common predators, have come to mimic each other's honest warning signals, to their mutual benefit. In fact, the key here is that the model actually benefits from being mimicked, because it can share the troublesome burden of enlightening the predator of its harmful properties. In this cooperative enterprise, both parties benefit. It could thus be classified as a form of mutualism, an ecological relationship where two species gain mutual advantage from a biological interaction; in this case via the signal receiver. 2023 Mimicry in insects 11 Mullerian mimicry

12. One of the most well-known examples of mimicry, the viceroy butterfly appears very similar to the noxious tasting monarch butterfly. Although it was for a long time purported to be an example of Batesian mimicry, it has recently been discovered that the viceroy is actually more unpalatable than the monarch, making this a case of Müllerian mimicry 20XX presentation title 12

13. 20XX presentation title 13

14. 20XX presentation title 14 In the same genus of Vespula where both are distasteful or harmful and closely resembling each other and therefore avoided especially by all their natural predators

15. Aggressive mimicry Automimicry 20XX presentation title 15 Other types of mimicry

16. Also known as PECKHAMIAN MIMICRY Aggressive mimicry is a form of mimicry in which predators, parasites, or parasitoids share similar signals, using a harmless model, allowing them to avoid being correctly identified by their prey or host. Zoologists have repeatedly compared this strategy to a wolf in sheep's clothing. One of the most interesting groups of ant mimics is spiders. some ant-mimicking spiders wave their front two legs over their heads so they look like antenna. The ants don’t seem to be fooled, however. Nevertheless, they will allow the spiders to hang around so long as they stay out of trouble. 2023 Mimicry in insects 16 Aggressive mimicry

17. The automimicry (also known as intraspecific mimicry) is a special case of mimicry that takes place when an organism transforms some part of its body in order to seems like another part of its own body or even of the body of another member of its species (e.g. a male that mimics a trait from females). The objectives of this type of mimicry are to obtain some benefit from other organisms or maybe to be unnoticed by their predators or preys. 20XX presentation title 17 Automimicry The northern pygmy owl ( Glaucidium californicum ) has two big dark spots behind its head which remind of two big eyes (picture by Michael Durham ).

18. Case study

19. 20XX presentation title 19

20. 20XX presentation title 20 To test whether vibrations generated by bugs aggressively mimic the vibrations generated by insect prey, they compared the responses of spiders to bugs with how they responded to prey. Objective

21. They collected juvenile and adult bugs from Macquarie University grounds on the day before testing . vinegar fly maintained in laboratory cultures, and Aphids that is often found in the webs of Achaearanea sp. in nature . For recording techniques they used sound-attenuating chamber (1.8 1.8 2 m) on a vibration-isolating table (Kinetic Systems, USA) under full spectrum lighting and fishers exact test. 2023 Mimicry in insects 21 Materials and Methods

22. Th ey found significant differences in the responses of spiders to the different vibration sources (Fisher’s exact test p , 0.01); How spiders responded to bugs was extremely similar to how spiders responded to prey (Fisher’s exact tests, vinegar flies versus bugs: (p=0.56); aphids versus bugs: (p=0.65); vinegar flies versus aphids, ( p=1.00). For both types of prey there were only two instances in which the spider made a direct approach. To assess spider responses to each of the treatments, they defined general sequences of spider response . 2023 Mimicry in insects 22 Result Figure . Responses of spiders to each vibration source. Significant differences are indicated by different letters (Fisher’s exact tests). Dark grey bar: direct approach. Grey bar: orient, pause, approach. Light grey bar: orient, no approach

23. 2023 Mimicry in insects 23 Figure 2. Representative waveforms of vibrations generated by ( a ) bug plucking web, ( b ) single aphid vibration making a small leg or body movement, ( c ) single vinegar fly vibration making a small leg or body movement, ( d ) aphid impacting web, ( e ) vinegar fly impacting web, ( i ) aphid wing beats in web and ( j ) vinegar fly wing beats in web.

24. conclusion Vibrations generated by bugs occupied a narrower band of frequencies compared with the much more variable and often higher-frequency vibrations from both types of prey. Rather than aggressively mimicking a specific prey model, bugs are best interpreted as general mimics that exploit a bias in spiders to approach prey-like vibrations in the web. Overall aggressive mimicry is an intriguing phenomenon in insect ecology that holds exceptional potential for scientific research . By studying aggressive mimicry, we can gain a better understanding of the complex interactions between species in their natural environments. 2023 Mimicry in insects 24

25. THANK YOU