Question about breeding

If you were to breed a Lesser Bee to a Spider you get this.....But what I don't understand is, you get 12.5% - 1/8 Lesser Bee and you also get 25% - 2/8 Lesser Bee. Why is it not calculated together? Is there a difference?

12.5%	1/8	Normal
37.5%	3/8	Spider
12.5%	1/8	Lesser
12.5%	1/8	Lesser Bee
25%	2/8	Lesser Bee

I have been breeding for many years and I never use charts because at the end of the day its a roll of the dice

That's just the way that particular calculator works. It's calculating the odds of producing a lesser bee from the spider x lesser (from the lesser bee) and the odds of producing a lesser bee from the lesser bee itself if that makes any sense.

In reality you would just add both together to get the ⅜ chance per-egg of getting a lesser bee.

Since there are 2 genes at play in the lesser bee, it calculates the chances of getting:

1. Spider with the lesser gene
and
2. Lesser with the spider gene

That's why it splits them up in to two