This is wrong. Animals "fressen". They don't "essen", the latter is what people do. Therefore, if the bug was eating the lunch, it would HAVE to be "Das Insekt frisst das Mittagessen." Otherwise, only "Das Insekt ist das Mittagessen." can be correct. It's disgusting (The insect is the lunch), but it's the only option.
Would fressen roughly translate to feed on or have any relation to foraging?
Is essen applied mainly to 'people food' and fressen more to 'animal food' or does it relate more to the creature doing the eating, or the manner thereof?
When fressen is used of a person, what does it refer to? What they are eating? (food usually eaten by an animal, or only fit for an animal?) Eating like an animal? (with no utensils? messy?) Eating as much as an animal? As fast as an animal?
If you were to say someone is eating like a particular animal, say a pig, horse or bird, would you use fressen or essen? Would you use fressen for eating like an animal in a non-insulting manner? (Eating like a bird, while slightly negative, is not really insulting.)
essen or fressen is chosen according to the subject. When people eat anything, use essen. When animals eat anything, use fressen.
When fressen is used for a person, e.g. "Peter du isst nicht, du frisst!" It means that person is eating like an animal or eating in excessive quantities like at your friendly local scarf & barf buffet.
For "You eat like a bird", you could really use either. "Du isst wie ein Vogel." or "Du frisst wie ein Vogel." Although I'd probably go with the former as it's not really meant as an insult.
With animals, "fressen" is the USUAL choice, but "essen" is not wrong. With people, "essen" is the CORRECT choice; "fressen" is wrong, unless you want to insult or criticize someone. English has a similar distinction with the nouns "food" and "feed." A rancher buys feed for his cattle, not food. "You eat like a bird" would be "Du isst wie ein Vogel" and means you eat very little. I suppose if the person bobs his or her head and pecks at the food, that would be "Du frisst wie ein Vogel." Duo's sentence could mean that one insect eats the entire lunch. Since that seems unlikely, perhaps it actually means the insect is eating the lunch.
It should be accepted. The English word “dinner” usually refers to the main meal of the day, which is typically taken either around midday or in the evening, depending mainly on the culture. In the German-speaking world, the midday meal is traditionally the main meal, although evening dinner is becoming more common as work patterns (such as longer commutes) change.
[Interestingly, the word “dinner” derives from the Latin word for “breakfast”, ‘disjejunus’, back when Romans had only two meals a day, and broke their fast at midday.]
And we have a breakfast (earlier morning meal), dinner (midday main meal) and evening (18-19pm meal) in Russia. Often we have 'an afternoon snack'. And children has '5th meal' before going to bed in the children's holiday camp) And I did not realize for a long time why the English have mean male an evening..o_O