If by animal collective you mean a literal collective of animals, then a sedge.
If, on the other hand, you mean a song by Animal Collective: "Seal Eyeing." ;D
Sedan, seize, sense, setup and seven are 5 letter words that begin with the letters se.
send send sea segal season self september second secret seven search serious
Serge is a worsted fabric that begins with the letters se.
Some animals, such as those in the genus Hydra, don't actually have a brain per se, making it difficult to answer.
Se~nora
Seattle
secretary
seize, seizure,
A word. Many groups of letters is called a sentence(:
some words are begin with the prefix se- include:seducesecede (yes this is a word)secludesecureand many more just go on this sitehttp://www.wordinfo.info/words/index/info/view_unit/1922/
"It is spelled" = "Se escribe... (letters here)"
se...haring