In lime butterfly(Papilio demoleus) what could be the reason behind the basal color change in both wings?

[pranavdatar]

Just a few days before, I saw a lime butterfly fluttering over barren land. Then after some time I saw another lime butterfly, but this one’s wings had brown colored base. initially I

thought this color change must be related to sexual dimorphism or just simply polymorphism. But when I

searched more about the butterfly, I came to know that older adults of lime butterfly are a bit different from young adults with respect to coloration(on wikipedia, https://en.wikipedia.org/wiki/Papilio_demoleus). What could be the reason behind this color change? I am attaching both the photographs of both lime butterflies here. Also note the minor wing damages on older adult(also supports the thing that this one is more older?).

[ececc]

Hi,
i’m from italy and I’ve been breeding Papilio machaon for over 10 years. I noticed that the colors on the adult’s wings can be a bit different, depending on the feeding plant of the caterpillar. When i see some wild butterflies that look old (damaged wings) they often appear with faded colors.
I don’t know if it’s the same with your species (so that would mean it’s the opposite theory), what i typed above is all from my experience and not knowledge of the butterfly biology. Let’s wait some expert to show up

[fffffffff]

Can you see if the wing is intact in the older specimen? Can it be the actual wing surface is yellowish and when cover is worn out it’s shown like that?

[naturalist_aditya]

I’ve observed myself many times, older specimen tend to have darker colours, though I don’t really know about the reason behind it.

[karthikeyaeco]

The same way as you have observed,I found a lime butterfly in my garden,its base was like blackish colour and its wings were very light yellow [https://www.inaturalist.org/observations/93447998]