Grasshoppers and Grass Feeding

There are over 10,000 species of grasshoppers (Acrididae) that are differentiated by climate, location and plant feeding preference. Some species are specialists on grass; some are specialists on forbes; and some are generalists feeding on both grasses and forbes. The chewing mouthparts of the grasshopper, the mandibles, have different adaptations to the different plants groups*.

The mandibles of all grasshoppers are asymmetric, with the left overlapping the right when the mouthparts are closed. The lower part of the mandible contains the edge used to cut plants into pieces small enough to swallow. The cutting edge often incorporates zinc or other metals to increase its hardness and make a sharper edge. This edge is differentially adapted in forbe and grass feeders.

Grasshopper Mandibles

Grasshopper Mandibles
Top: Forbe Feeder
Bottom: Grass Feeder After Isely 1944*

In forbe feeders, the mandible has jagged teeth, similar to a serrated knife. The mandibles “punch” a leaf piece from the edge when they close. In grass feeders, the cutting edge of the left mandible resembles a smooth knife blade. The “teeth” are closely apposed and separated by only a shallow grove. In some grass feeding species, the teeth form a smooth cutting surface without grooves. These mouthpart adaptations can limit the ability of some grass feeders to effectively feed on forbes.

*Isely, F. B. 1944. Correlation between mandibular morphology and food specificity in grasshoppers. Ann. Entomol. Soc. Am. 37:47–67.

About jjneal

Jonathan Neal is an Associate Professor of Entomology at Purdue University and author of the textbook, Living With Insects (2010). This blog is a forum to communicate about the intersection of insects with people and policy. This is a personal blog. The opinions and materials posted here are those of the author and are in no way connected with those of my employer.
This entry was posted in by jjneal, Environment, Taxonomy. Bookmark the permalink.

One Response to Grasshoppers and Grass Feeding

  1. Pingback: Grasshoppers and Grass Feeding | Living With Insects Blog

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s