Crocodile egg sounds signal hatching time Amélie L. Vergne, Nicolas Mathevon  Current Biology  Volume 18, Issue 12, Pages R513-R514 (June 2008) DOI: 10.1016/j.cub.2008.04.011 Copyright © 2008 Elsevier Ltd Terms and Conditions

Figure 1 Behavioral responses of Nile crocodile embryos and adult females to sound playback. (A) Embryos show higher behavioral activity — in terms of emitted vocalizations and movements — during playback of pre-hatching calls than during playback of noise or silence period. ∗ (P < 0.05); ∗∗ (P < 0.01). (B) Crocodile mothers react strongly to playback of pre-hatching calls, most of them by digging the sand. ∗ (P < 0.05); ∗∗ (P < 0.01) (ns: not significant) See also Supplemental Movie. Current Biology 2008 18, R513-R514DOI: (10.1016/j.cub.2008.04.011) Copyright © 2008 Elsevier Ltd Terms and Conditions