Easier to grow than to spell, Eschscholtzia californica, the state flower of California, is the botanical visual equivalent of a perfect, sunny-side-up egg yolk.... and there is an indirect link between orange flowers like this and egg yolks.
Birds can't make the yellow cartenoid pigment that's a component of petal colour in California poppy and many other yellow-flowered plants, so all the yellow pigment in birds' plumage and egg yolks has to come directly from the plant food that they eat, or indirectly from animals that they eat that have in turn eaten plants with the yellow pigment. For example, blue tits that have eaten caterpillars that have eaten plants deposit the yellow pigment in their breast feathers - so a blue tit that has bright yellow feathers is likely to be a good caterpillar hunter. It has been know for poultry farmers to feed orange marigold petals to hens so that they produce eggs with more intensely yellow yolks.
Mammals can't make carotenoids either so plant carotenoids are the source of vitamin A which is a vital human visual pigment, which is why carotenoids have been genetically engineered into Golden Rice, to help prevent blindness in communities that have low levels of vitamin A in their diet.
Aside from its glorious golden flower colour, California poppy has very attractive glaucous green, feathery foliage. I grew it in my garden last year and was delighted to find that it had self-seeded and that they seeds had survived our recent hard winter. Little glaucous green seedlings are coming up all over the garden.