This is a brittlestar:

Closely related to the starfish, the brittlestar is also known as the serpent star because of the five long tentacle-like arms that extend from its central body. Found in the deep waters of all marine areas, the brittlestar is an interesting creature in that it has no eyes or other specialized sense organs. The entire brittlestar is its own sense organ. Its entire skeletal systemis covered with roughly ten thousand calcite crystals that “collect and focus light directly onto nerve bundles that are part of the brittlestar’s diffuse nervous system. Remarkably, the brittlestars secrete this crystalline form of calcium carbonate (calcite) and organize it to make optical arrays” (370). Basically, the brittlestar’s skeletal system is composed of microlenses that, in combination with its nervous system, function as a compound eye. In Meeting the Universe Halfway, Barad uses the brittlestar to illustrate her theory of agential realism. I will attempt to summarize her discussion of agential realism and the brittlestar in the remainder of this post.

Sight is the privileged sense among human beings for certain. “Seeing is believing,” right? But sight for us tends to represent a barrier between the seeing subject and the object (the eyeball) doing the seeing. For brittlestars, that division doesn’t exist. They, the entire being that is the brittlestar, are eyes. Barad writes, “It is not merely the case that the brittlestar’s visual system is embodied; its very being is a visualizing apparatus. The brittlestar is a living, breathing, metamorphosing optical system. For a brittlestar, being and knowing, materiality and intelligibility, substance and form, entail one another” (375).

Not only is the brittlestar a seeing body, it is also capable of changing its color in response to the available light in its surrounding (important for eluding predators for certain). It can also break off a portion of its body and regrow that portion (brittlestar, get it?). Now, I think all of that is pretty amazing in and of itself, but Barad uses the brittlestar’s “ongoing reworking of its bodily boundaries” to discuss material-discursive practices (375). She writes:

Its [the brittlestar] discursive practices- the boundary-drawing practices by which it differentiates itself from the environment with which it intra-acts and by which it makes sense of its world, enabling it to discern a predator, for example- are materially enacted. The brittlestar’s bodily structure is a material agent in what it sees and knows as part of the world’s dynamic engagement in practices of knowing. Similarly, its bodily materiality is not a passive, blank surface awaiting the imprint of culture or history to give it meaning or open it to change; its very substance is morphologically active and generative and plays an agentive role in its differential production, its ongoing materialization. (375-6)

The brittlestar (re)configures its bodily boundaries based upon its intra-activity with its world. This animal beautifully demonstrates the notion that bodies are not situated in the world but are part of the world (376). Bodies are not things, bodies are performances.

For more information on the brittlestar, see Eyeless Creature Turns Out To Be All Eyes

(images courtesy of Google Images, search term “brittlestar”)