Willpower?

A large chicken vs. a small chicken?

Alot of hard work!

Ah, size and weight of the egg. There are six U.S. weight classes for the consumer grades of shell eggs--Jumbo, Extra Large, Large, Medium, Small, and Peewee. The classes define the minimum net weight per dozen eggs. Graders check shell egg weights during the grading process to ensure their accuracy.

a positive mental attitude?

dubble yock

Ahhh. The size...Just a guess?

The hen! Depends on how she lays that out!

There are local definitions for chicken eggs, according to the mass of the egg. I don't know of standard size definitions for eggs of other animals, although some of them are also used for food. In the USA, for instance: - Large (L): Greater than 2 oz. or 57g, but smaller than 2.25 oz. or 64g - Small (S): Greater than 1.5 oz. or 43g, but smaller than 1.75 oz. or 50g "Chicken eggs are graded by size, for the purpose of sales. The United States Department of Agriculture grades them by weight per dozen. The most common US size of chicken egg is 'Large' and is the egg size commonly referred to for recipes. The following egg masses have been calculated on the basis of the USDA grades: Modern Sizes (USA) Size Mass per egg Jumbo Greater than 2.5 oz. or 71g Very Large or Extra Large (XL) Greater than 2.25 oz. or 64g Large (L) Greater than 2 oz. or 57g Medium (M) Greater than 1.75 oz. or 50g Small (S) Greater than 1.5 oz. or 43g Peewee Greater than 1.25 oz. or 35g " Source and further information: http://en.wikipedia.org/wiki/Egg_%28food%29#Chicken_egg_sizes Please look at that page for other definitions in Europe, Australia and New Zealand. I found also Japanese egg size definitions: "LLサイズ 70g以上76g未満 赤 Lサイズ 64g以上70g未満 橙 Mサイズ 58g以上64g未満 緑 MSサイズ 52g以上58g未満 青 Sサイズ 46g以上52g未満 紫 SSサイズ 40g以上46g未満 茶 " Source: http://ja.wikipedia.org/wiki/%E9%B6%8F%E5%8D%B5

How bad it hurts on the way out. hahaha!

Ignore all other answers, especially that long winded one about sizes, weights etc, what a load of rubbish, Did,nt anyone read the question? The simple answer is "FOOD" More food, ergo larger eggs. This is done in battery farming by lengthening the length of time the artificial lighting is left on. Longer feeding time....more food....larger eggs. Incidentally the colour of the shell can be changed just by adding colouring to the feed. So those lovely brown shelled ones are very probably imposters.

size

the bigger the chicken the bigger the eggs.