What is the meaning of this rebus?

FEANCIENTFE

Each of the following sentences contains clues to a set of three words that are anagrams of each other (each sentence describes a different set).

1) I have a painting of a small mammal wearing a coating without the feathers.

2) A winged apparition will harvest the grain where the two lines intersect.

3) The members of the two groups were fearful of the Holy Grail.

4) Trying to reach home and score the winning run, Joe jumped over the ...

Six words have had their birds removed. The birds have been placed into Group A. The remaining letters of each word have been placed into Group B. Your task is to reconstitute the words by merging each bird with the proper set of letters. Other than merging the two groups together, there is no rearranging of the letters. Example: sand + pne = spanned (SpANneD).

Group A: crow, hawk, owl, raven, robin, wren
Group B: itt, ndior, ossb, tre,...

Letter Equations are well known phrases or facts where the key words have been replaced with the first letter of that word. These are often in the form of an equation, which contain a number, an = sign and the rest of the obscured phrase or fact.

1 = H on a D C

Six words have had their colors removed. The colors have been placed into Group A. The remaining letters of each word have been placed into Group B. Your task is to reconstitute the words by merging each color with the proper set of letters. Other than merging the two groups together, there is no rearranging of the letters. Example: sand + pne = spanned (SpANneD).

Group A: blue, brown, cyan, green, pink, red
Group B: agssivess, astr, ...

Which element in Group B can be added to Group A? Why?

Group A: Iridium, Vanadium, Xenon, Lanthanum, Carbon, Dysprosium
Group B: Radon, Barium, Uranium, Platinum, Manganese, Phosphorus