animal's relationship with its environment. The umwelt is for him an environment-world which is, according to Agamben, "constituted by a more or less broad series of elements [called] 'carriers of significance' or 'marks' which are the only things that interest the animal". Agamben goes on to paraphrase Uexküll's example of the tick, saying: "...this eyeless animal finds the way to her watchpoint [at the top of a tall blade of grass] with the help of only its skin’s general sensitivity to light. The approach of her prey becomes apparent to this blind and deaf bandit only through her sense of smell. The odor of butyric acid, which emanates from the sebaceous follicles of all mammals, works on the tick as a signal that causes her to abandon her post (on top of the blade of grass/bush) and fall blindly downward toward her prey. If she is fortunate enough to fall on something warm (which she perceives by means of an organ sensible to a precise temperature) then she has attained her prey, the warm-blooded animal, and thereafter needs only the help of her sense of touch to find the least hairy spot possible and embed herself up to her head in the cutaneous tissue of her prey. She can now slowly suck up a stream of warm blood." Thus, for the tick, the umwelt is reduced to only three (biosemiotic) carriers of significance: (1) the odor of butyric acid, which emanates from the sebaceous follicles of all mammals; (2) the temperature of 37°C (corresponding to the blood of all mammals); and (3) the hairy topography of mammals. Critics Uexküll's application of the notion of "umwelt" to the human person has been contested. In "Welt und Umwelt" and "Die Wahrheit der Dinge", the philosopher and sociologist Josef Pieper argued that reason allows the human person to live in "Welt" (world) while plants and animals do indeed live in an Umwelt—a notion he traces back far beyond Uexküll to Plato, Aristotle, and Thomas Aquinas. See also References Further reading Naming Natureby Carol Kaesuk Yoon View from the Oak by Herbert and Judith Kohl The New Press | https://thenewpress.com/books/view-from-oak An Immense World by Ed Yong Penguin books Vintage | https://www.penguin.co.uk/books/440513/an-immense-world-by-yong-ed/9781847926081 External links Umwelt by John Deely Umwelt and Phenomenology Umwelt and semiosphere by Kalevi Kull Pragmatism and Umwelt-theory by Alexei Sharov TDE-R - A Subjective Biocomputer by Charles Dyer Semiotics Neuroethology concepts Existential