Why do maggots eat dead flesh?

Question: Why do maggots eat dead flesh?
- Keywords:
  flesh,
  maggot
Asked by peter296 to Tommy, Sonia, Simon, Ollie, Jean, Brian on 28 Apr 2020.
- Brian Murray answered on 28 Apr 2020: last edited 28 Apr 2020 3:37 pm
  
  Hi Peter,
  Great question. Sometimes the yuk ones are kinda cool…
  
  I did a bit of reading on this for you, because I didn’t know the answer. All I knew is that scene from Gladiator where they use them on his wound to help the healing!
  
  It turns out that maggots eat their food differently to us. While we eat it and then digest it, they do it the other way around – they digest it first and then eat it! They secrete enzymes on the bits they want to eat so that it breaks down for them. This is called “extracorporeal digestion”. It’s thought that the dead tissue is already weak and breaking down, so it’s easier and faster for them to focus on this instead of the living tissue.
  
  Hope this answers your question?
  
  Brian
- Simon Spichak answered on 28 Apr 2020:
  
  Maggots are the larva of specific flies (kind of like caterpillars and butterflies). Now the food source for these flies is rotting meat, they are attracted to some of the smells released by this meat. They lay their eggs there, so that when they hatch – the maggots have plenty of food to eat. The maggots take a few days to stock up on all those nutrients and proteins. They can use these nutrients to help develop the machinery they will need to slowly transform into flies! Believe it or not, people used to think that maggots spontaneously appeared on rotting flesh – but now we understand that it’s just a part of their interesting (and smelly) life cycle.
- Tommy Hayden answered on 28 Apr 2020:
  
  Hi Peter
  
  I’m not sure but my opinion on evolution is that it’s a mix of coincidence and balance. Things that survive need to have the right conditions for their survival. Generally this seems to align with their existence being useful to other things
  
  Maggots digestive systems seem to be a lot different to ours. Apparently they effectively eat their own excrement. Their secretions break down dead tissue into a liquid that they then consume. Those secretions don’t break living tissue down in the same way that dead tissue breaks down
  
  I’m assuming they have successfully survived for so long on account for there not being huge competition for their food source
  
  If they stayed in maggot form for their full life they might struggle to get from one bit of dead flesh to another but since they turn into flies that addresses that challenge
  
  I’d like to have the power of flight but they’re welcome to it considering the stuff they have to go through…