Crocodiles that ignore birds cleaning their teeth instead of eating them is an example of habituation.
<h3>Crocodile and avian mutualism—is it real?</h3>
One of nature's best instances of mutualism is the interaction between a Nile crocodile and an Egyptian plover bird.
A crocodile will simply open his mouth and wait when he needs to floss.
The plover bird will involuntarilyswoop down and grab meat scraps from the crocodile's gaping jaws.
<h3>Why do crocodiles develop a habit of approaching the birds that brush their teeth?</h3>
It is a phenomenon of evolution that when a bird used to sit in a crocodile's mouth, the crocodile didn't eat it; instead, the crocodile used to allow the bird to sit in the mouth and clean the crocodile's teeth so that they can live longer, whereas the birds could get the free food from the crocodile's mouth.
It is an illustration of how the two are mutually beneficial.
The same is true now because crocodiles have adapted to the fact that birds will clean their teeth, so rather than consuming them, they ignore the birds.
This is because the GP120 protein
of the HIV virus that forms the ‘knob’ is
essential for the infection of CD4 cells
of the immune system by the virus. The glycoprotein is, therefore, a good
target for vaccines especially since the
molecule is highly conserved because most mutations in the region could be highly deleterious to the virus.
