False Behaviour

False Behaviour

The next level of deception in animals concerns the utilisation of false behaviour. Behaviour that conceals the true nature of the animals’ intentions. Such a predator acting in such a way that it hides it predatory nature around possible prey. These behaviours are more examples of aggressive mimicry as seen in the last blog.

Stenolemus bituberus (assassin bug) deceive spiders into thinking they are the prey rather than the predator. They hunt web-building spiders by plucking the silk of the web, generating vibrations that lure the spider into striking range. Wignall & Taylor (2010) describe that the assassin bugs mimic enough vibrations within the range of vibrations that are classified as ‘prey’ to the spiders.

Figure 1. Stenolemus bituberus exploring a spider web. Photographer: Anonymous (2005).

False behaviour techniques can also be utilised through the use of automimicry. Automimicry is when animals have one body part that mimics another in order to increase survival during an attack or to hide a predators intentions. Laticuda colubrine (yellow-lipped sea krait) appears to have two heads, however, it has evolved through successful use of automimicry to have a tail that looks and behaves like its head. This species of sea snake will intrude into nests looking for a meal exposing the behind unprotected to the environment. However, its tail looks and behaves like it venomous head deterring any would be predators. This species has combined false behaviour and automimicry in order to greatly increase its chances of survival. However, there are fitness trade-offs for such an advantages trait. Rasmussen & Elmberg (2009) describe that the tail needs to be flattened in order to move through the water but this would lead to the tail looking different to the head. We must remember that evolved traits may prove to be advantageous in one aspect but may hinder a species in another, and this will be explored in the future on this blog.

Figure 2. Laticauda colubrina displaying “both” heads. Photographer: Anonymous (2009).

References

1.     1. Anonymous. (2005). Stenolemus bituberus exploring a spider web. http://bio.mq.edu.au/research/groups/behavbiol/Assassins.html ; retrieved 05/04/2015.

2.     2. Anonymous. (2009). Laticauda colubrina displaying “both” heads. http://www.sciencedaily.com/releases/2009/08/090805201539.htm; retrieved 05/04/2015

1.     3. Rasmussen, A. R., & Elmberg, J. (2009). ‘Head for my tail’: a new hypothesis to explain how venomous sea snakes avoid becoming prey. Marine Ecology. 30, 385-390.

2.     4. Wignall, A. E., & Taylor, P. W. (2010). Assassin bug uses aggressive mimicry to lure spider prey. The Royal Society. http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=3061146.