Congratulations! Your embryo has started to develop. Even though you are still very far away from the adult form of the fly (imago), your body has started to become patterned into firstly 7 and then 14 segments that correspond to adult segments of the thorax and the abdomen.

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Time

The Corpus Christi Clock

Image credit: Samantha Wilson

The Corpus Clock was unveiled by Stephen Hawking in 2008 and it is one of the largest clocks running of a 'grasshopper escapement' mechanism in the world!

The clock is not operated by electricity but is powered by the movement of it’s pendulum which allows the hands (or golden rings) to spin and tell the time.

However, unlike a traditional clock, the Corpus clock is a little more sporadic with its time keeping! The grasshopper-like creature nicknamed Rosalind represents Chronophage (or “time eater” in Greek) - the clock is a reminder of the inevitable passing of time.

Our inner time-keepers

Confocal microscopy image of a developing fruit fly brain showing the neural stem cells in various colours, each corresponding to the presence of a different protein. Each protein can alter gene expression to tell the neural stem cell what type of neuron to become.

Our brains are full of an incredible diversity of cell types, including thousands of different types of neurons.

These are produced by neural stem cells before we are born and must be made at the right place and time to be able to undertake their functions after birth.

To do this, just as the Corpus clock measures the passage of time, neural stem cells must be able to accurately tell the time during embryonic development too!

Scientists at the Gurdon institute use the brains of fruit flies to explore the factors that allow neural stem cells to tell this sort of biological time. The Brand group and others have found that different sets of proteins are present within neural stem cells at different times. These proteins are able to control the genes that are active or inactive and ultimately tell neural stem cells what type of neuron to become.

Our hope is that by understanding the mechanisms that drive a neural stem cell to make one type of neuron or another, we will be able to find out what causes disorders in the human brain and come up with better treatment strategies and interventions.

  • Tick tock…. goes the clock but its time is a little off!

    Find the number of strikes per hour that this clock is accurate!

  • The Clock in front of you is not very good at telling the time accurately! Can you find out how many times an hour it is correct? (Hint: have a look for a sign to find your answer!).

*This answer is a number (not text).

“The universe doesn't allow perfection.”

— Stephen Hawkin, A Brief History of Time