We investigate the?evolution of clumpy galaxies with?Hubble Space Telescope (HST) samples of ~17,000 photo-z and Lyman break galaxies at z 0–8. We detect clumpy galaxies with off-center clumps in a self-consistent algorithm that is well tested with previous study results, and we?measure the number fraction of clumpy galaxies at the rest-frame UV, . We identify an evolutionary trend of over z 0–8 for the first time: increases from z 8 to z 1–3 and subsequently decreases from z 1 to z 0, which follows the trend of the?Madau–Lilly plot. A low average Sérsic index of n 1 is found in the underlining components of our clumpy galaxies at z 0–2, indicating that typical clumpy galaxies have disk-like surface brightness profiles. Our values correlate with physical quantities related to star formation activities for star-forming galaxies at z 0–7. We find that clump colors tend to be red at a small galactocentric distance for massive galaxies with . All of these results are consistent with the picture that a majority of clumps form in the violent disk instability and migrate into the galactic centers.
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