Merleau-Ponty’s discussion of Uexküll occurs in the second of his three Collège de France lectures on nature. The question that animates the lectures is the nature of the totality that constitutes an organism. Merleau-Ponty argues that this totality is immanent and emergent, and that, following Uexküll, it includes the relation an animal has with its Umwelt. However, despite the use Merleau-Ponty makes of Uexküll’s Umwelt concept, there are important differences. Whereas Uexküll’s “natural factor” is a transcendental nature-subject, Merleau-Ponty conceives nature’s directing principle as a “theme” that cannot be separated, metaphysically, from the immanent unfolding of the history of life. As a result, while the expressiveness of nature, for Uexküll, occurs at transcendental level, Merleau-Ponty enquires into the natural history of expression, and symbolic, ritualistic behavior, as it is manifest in the lives of animals. This inquiry lays the foundation for a conception of “inter-animality,” which extends the totality in question from a preestablished collection of species-specific environments to a “Lebenswelt,” unified by a shared, intercorporeal understanding of nature’s “system of signs."