Shopping for new homes: The struggle of hermit crabs for shells 

When you belong to the middle- or low-income group, rented house is the only option for you in Dhaka. Scanning the "to let" signs you keep searching for a suitable – though impermanent – abode. The wealthy too worry about their houses. They fret over the design and facilities they would like to have, besides making sure that they remained big and posh. Interestingly, human beings are not the only ones who need a home and troubled by the problems of accommodation. Like humans, hermit crabs, are also badly in need of a home for their safety – and like their human counterpart are faced with competition and inequality. 

A documentary has revealed how this creature with ten legs picks up their homes in a disciplined manner from castoff shells on beach. Though, like most city dwellers they do not have the privilege to choose or design their own homes. In fact, they have to depend on other creature's mercy for their home. 

This species has a fragile body with soft abdomen. Being directly exposed to nature makes them too vulnerable. 

Sadly, they do not have a shell of their own to protect themselves. So they depend on the shells left by other creatures. Most of the time they depend on snail shell. Again they grow with time and with their physical growth the previous shell turns out to be inadequate. This is when the necessity to upgrade or shop a new home comes. 

The process of their moving to new homes can be very surprising to observe. Often the shells they get on shore are way bigger than their size. So, they make a que from the smallest to the largest one and keep trying out the shells one by one. 

When they spot a perfect fit they compete with one another for it. When the biggest one tucks itself into the shell, others focus on the next available shell size. Sometimes a defective shell is left for the smallest crab. For them a defective shell is always better than no shell. 

It is not like they wait for snails to cast-off the shells. Sometimes they move out to the ones left by another crab who has recently upgraded to a bigger shell. 
Sometimes they kill snails for their shell and sometimes they drive existing ones out of their place for their own survival.