Over last 5 million years the wild budgies with red, orange, pink colours had been weeded out by falcons, because they stand out against green, brown surroundings.
Budgies are related to lorikeets & lories which had red, pink, orange colours.
5 million years ago when climate in Australia had became dry and numbers of flowering plants decreased, replaced by grasses, the lorikeets had a hard time trying to surivie, but the smaller lorikeets switched from flowers, to seeds and started to eat the seed heads of grasses, these lorikeets and early budgies had red, pink, orange colours.
Seaval genes of lorikeets were eating seeds, but their grizzards cannot deal with seeds and grits very well, so lorikeets were going toward extinction & fell prey to falcons, but before they became extinct, their mutation lorikeet chicks arrived against lorikeet chicks, and the lorikeets bred for first time, cared for mutation chicks, and taught the juveniles to eat seeds and flowers, but mutation chicks wants seeds and not interested in flowers, to their lorikeet parents"s dismay. So they drove their mutation chicks away.
The mutation chicks were wild budgies and as climate became drier, with grasses became plentliful. Budgies"s grizzards can deal with seeds and hard foods as tree barks.
Lorikeets became extinct, but their future geneations...WILD BUDGIES surivied and increase their numbers. The falcons find budgies much more difficult to hunt & catch than lorikeets, but seaval years the falcons learnt to hunt the budgies.
The wild budgies with red, orange, pink colours were chased & caught by falcons, but mutation budgies withOUT red, orange, pink colours were not been caught as they are not eye-catching. Mutation budgies surivied and increase their numbers, while budgies with red, pink, orange colour became extinct, along with their DNA for red, orange, pink colours. This left green, black, yellow budgies remained alive and carry on surivied to today.
The purple cheek patches and wing stripes, intelligence, playness are reminder of lorikeets.
If you look at budgies DNAs to look for red, pink, orange genes, it will be like finding a pin in a hay stake, so 1 or 2 budgies against thousand millions budgies, have red, pink, orange colours. With no genes for red, orange, pink colours, there is no way we will have pink, red, orange budgies in future.
Hybridize the budgies with Bourke's parrots, may not produce healthy chicks.
There is nothing we can do to breed pink, orange, red budgies.
Lorikeets, 6 million years ago when Australia climate similar to today New Guinea climate. Eat fruits and flowers. Started to produce mutation lorikeets, when climate started to dry. Purplish blue heads, with red caps.
Mutation lorikeets (early budgies), 5 million years ago when Australia climate started to dry, with disappeance of fruiting & flowering trees. Eat seeds of grasses (become available to early budgies). Falcons becoming common.
Still had red underwings.
Today's budgies, 5 million years later, lost all red colours, through weeded out of existance by falcons. Eat seeds. Falcons common.
Once genes for red, orange, pink colours are lost, cannot be replaced.