In the summer I was tasked with setting up an outreach activity to fit in with the Cardiff University STEM event themed around Life on Mars aimed at year 8 pupils (12/13 year olds). The invite was to all STEM schools and incorporated Biosciences, Chemistry, Physics, Computer Science, Maths and more. So I set my mind to what we could do on topic for a place renowned for its lack of life (so far!).
The underlying principle of the DNA Guess Who! activity was to explain the connection between a DNA sequence and the observed phenotype (i.e. ‘DNA is instructions’) and I set to retooling it as an example of an environmental DNA survey of a barren landscape in-fitting with the theme. With a region to search, a battleship-style peppering with simulated 12 base sequences, and a decoding computer for species identification, we had a DNA treasure hunt on our hands.
After a fair amount of work building a Mars-esque terrain, habitat pods, and coloured straws acting as DNA sequences, we were good to go (photo album, polystyrene everywhere). Obviously, we can’t go around telling the students that we’re actually finding life on Mars, so the plan was to develop a ‘test site’ for the proto-astronauts to hone their DNA decoding skills on.
On top of the spaced out (waaay, pun!) DNA sequences corresponding to various potential Martian inhabitants, we had some dangerous things (Salmonella in the kitchen pod), and the cautionary tale of finding ‘human-related DNA sequence’ in the field (aka contamination). On top of the full sequences, the students could search the terrain, test module bedrooms, kitchen or W.C. and build consensuses from incomplete ones mastermind style.
On the day we set up in the Sherman theatre, decked out in Mars themed banners, red light, and a spacey soundscape. Mission control was in the adjacent building with a more Earthy environment. The students rotated between the different schools in 20 minute blocks and we gave them an onverview and set them on their mission. Turns out we were working to a bit too complex of a concept to get across in 20 minute sessions so we mainly stuck to the complete sequences, but we got the message across!
Once they had the sequences translated from the magnetic straws via the 3D printed Mars Rovers into the ‘DNA signal’, they had to move it around to the decoding computers to find out what the sequence coded for. This was a little perl script which added some theatrics to the dictionary lookup, and then some fact sheets about the species found to act as discussion points.
All in all, the students seemed very on board with the activity and we held our own alongside the obviously very exciting Nerf gun and explosion-based activities from the other schools!
For more photos from the day check out this album (we were too busy to take too many photos unfortunately 😦 ) and I’ll be adding a materials and methods document similar to the Guess Who! page shortly.