Folding Airbulb

The folding airbulb split from its ancestor, the airbulb. Its trunk has grown wider and shorter in proportion to its total body size, and the bulb has become more cylindrical. During the frigid winter, the ammonia will leave the bulb and cause it to fold down over the stalk, decreasing heat loss. Other than that it has not changed markedly from its ancestor, besides growing ten times its size.