Eight figures, nineteen kinds — what does a paper speak with?
PNAS 2025 “DDX54 …”, Figs. 1–8, counted panel by panel
Line up the kinds of chart in a single paper and this is what you get. Bars come first, hand-drawn schematics second.
Open a paper published in PNAS in 2025.
The story is that switching off a gene called DDX54 makes immunotherapy
start working in lung cancer. Twelve pages of text, eight figures.
Count those eight figures panel by panel and you get 62 panels.
Between them they use nineteen distinct kinds of chart.
This course redraws all nineteen, one at a time.
Not so that you can read this paper — so that you can draw yours.
Whether it is biology or a sales report, there are only so many ways a person
can look at a number.
All 62 panels of the paper's eight figures. Click a kind to see where it is used.
The most-used chart is the simplest one, the bar.
That is the first fact this course hangs on to.
One call to value_counts() gives the counts per kind — which also happens to be the syllabus of this course.
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The eight figures also do different jobs.
🗺️
Figs. 1–2 · we found it
picking DDX54 out of a crowd of candidates. Bars and violins do the work
🔬
Fig. 3 · how
what that gene actually does. Volcano plot and network
🐁
Fig. 4 · for real
does it work in a mouse. Growth curves and survival curves
☁️
Figs. 5–8 · what changed
what happened inside the tumour. UMAPs and dot plots
So the kind of chart tracks the stage of the research.
Bars when you are searching, boxes when you are comparing, volcanoes when you
are digging, UMAPs when you are showing.
🤔 Check yourself
Which kind of chart is used most often in this paper?
Answer 14 of the 62 panels are bars. The glamorous UMAP appears 4 times and the pie chart exactly once. The simplest chart is the most used one — because length is what people read best.
🤔 Check yourself
Nine of the 62 panels are schematics. What sets a schematic apart from the others?
Answer A schematic draws an experimental design or a mechanism instead of describing it in words. There is not a single number in it. So a schematic is never judged 'wrong' — only 'unconvincing'.
