...while the outside resembles a termite mound: https://www.pinterest.co.uk/pin/83175924339644023/ https://www.pinterest.co.uk/pin/83175924339644023/ (hat tip

...while the outside resembles a termite mound: https://www.pinterest.co.uk/pin/83175924339644023/ https://www.pinterest.co.uk/pin/83175924339644023/ (hat tip: Daniel Dennett)