Extended Data Fig. 4: Light spectra and intensity data for experimental light sources.

(a-e) Light intensity and spectra measured using an ILT950 spectrometer (International Light Technologies Inc, Peabody, USA) for (a) standard worm culture illumination, (b,b’) worm culture using ‘NELIS’ in linear plot (b) and logarithmic plot (b’), (c,c’) Behavioural chamber with ‘Nelis’ white light with UVA as linear plot (c) and logarithmic plot (c’). (d,d’) Behavioural chamber with ‘Nelis’ white light and a filter reducing light below 430 nm (UVAR filter, Pixelteq, Salvo Technologies, USA) as linear plot (d) and logarithmic plot (d’), (e,e’) Behavioural chamber with ‘Nelis’ white light matching the intensities of the spectrum >430 nm from (d,d’) as linear (e) and logarithmic plot (e’). Purple dotted line in b-e indicates the c-opsin1 high activation range. (f,g) Picture details of ‘Nelis’ light source.