For animals other than mammals, then, feeding is not intrinsic to parental care. Animals add it to their reproductive strategies to give them an edge in their lifelong quest for descendants. The most vulnerable moment in any animal's life is when it first finds itself completely on its own, when it must forage and fend for itself.
Does the word "quest" in this paragraph mean "search"?
Why animals search for their descendants?
'Quest for descendants' => sex. To quote the song 'Birds do it; bees do it. Even educated fleas do it...'.