A few tweaks and fixes:

• Critters mistakenly had differing energy caps when mature/immature. While there is some realism argument for juveniles having bottomless stomachs, this was unintentional and now Critters of any age have energy caps equal to their maximum health. You may find this makes it more difficult for new populations to ramp up -- consider increasing the value of food or reducing reproduction costs/thresholds if you become impatient.
• Nuts can now be deleted with the Delete tool or middle mouse
• The benefit of protein is increased (Critters who eat meat or nuts stay full longer)