Embryonic development of human lice

If you have kids, you probably already know all about lice. Or maybe you think you know all about lice – and you just want to crush it. But wait, just wait a second, pull out your foldscope next time anyone talks about lice and give it a good strong look. And you can crush it afterwards. Here is a highly adaptive animal that finds a way to your head, claws on, and reproduces on your head laying eggs (nits). Now, these eggs need to develop into a full adult – on your head. And hundreds of these eggs might be developing from a “single cell” into a complex fully functional animal capable of reproducing.

The process of embryonic development is remarkable – but it’s often hard to observe since embryos are very delicate and get disrupted during observation. Not in the case of human lice; here I document the entire process of observing development and embryonic stages of human lice – and the stages are absolutely fascinating.

The first common stages I could observe while searching for lice on my kids head (probably I have them too – I just don’t know it).. it starts with a stage with loose set of cells (looks like imaginable discs) that are alive and moving around. The next stage I start seeing several set of features. It follows a stage where the lice does tremendous amount of work pumping gas into its tracheal system and also detach itself from the cuticle. In my next series of posts – I will spend a lot more time on the dynamics of this gas pumping – but for right now – enjoy the beauty of this development process. And when you are done with it – feel free to crush it if it makes you feel better.

You can read more about the common nature of head lice on the CDC site.


Down below is data collected with time lapse; where I use “lapse it” as an app to collect very long time scales (maximum single time lapse collected is 12hrs). Since it takes 8-9days of development before lice eggs will hatch, I am yet to capture the hatching process. But I still was able to observe some remarkable details that I will share in upcoming posts.

Time lapse data on human lice development

10hrs in 5 sec

1hr in 5sec

3500sec in 60sec

64min in 10sec

1200min in 2min – watch the pumping of air for separation of the embryo from the cuticle

When life gives you lemons, make lemonade. When kids bring lice at home, observe embryonic development!

Keep exploring.


2 Comments Add yours

  1. Akib says:

    It is the head lice (pediculus humanus capitis). Can it work (observation of embryo development without much trouble) for the other two lices that affect humans too (Pthirus pubis and pediculus humanus humanus)? Or it will work for all >5000 species of lice?

  2. Manu Prakash says:

    Absolutely. Why not? 5000 specoes – wow


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