Orchestration : the movement and vocal behavior of free-ranging Norwegian killer whales (Orcinus orca)

Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy at the Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution June 2008Studying the social and cultural transmission of behavior among animals helps to identify patterns of interaction and information content flowing between individuals. Killer whales are likely to acquire traits culturally based on their population-specific feeding behaviors and group-distinctive vocal repertoires. I used digital tags to explore the contributions of individual Norwegian killer whales to group carousel feeding and the relationships between vocal and non-vocal activity. Periods of tail slapping to incapacitate herring during feeding were characterized by elevated movement variability, heightened vocal activity and call types containing additional orientation cues. Tail slaps produced by tagged animals were identified using a rapid pitch change and occurred primarily within 20m of the surface. Two simultaneously tagged animals maneuvered similarly when tail slapping within 60s of one another, indicating that the position and composition of the herring ball influenced their behavior. Two types of behavioral sequence preceding the tight circling of carousel feeding were apparent. First, the animals engaged in periods of directional swimming. They were silent in 2 of 3 instances, suggesting they may have located other foraging groups by eavesdropping. Second, tagged animals made broad horizontal loops as they dove in a manner consistent with corralling. All 4 of these occasions were accompanied by vocal activity, indicating that this and tail slapping may benefit from social communication. No significant relationship between the call types and the actual movement measurements was found. Killer whale vocalizations traditionally have been classified into discrete call types. Using human speech processing techniques, I considered that calls are alternatively comprised of shared segments that can be recombined to form the stereotyped and variable repertoire. In a classification experiment, the characterization of calls using the whole call, a set of unshared segments, or a set of shared segments yielded equivalent performance. The shared segments required less information to parse the same vocalizations, suggesting a more parsimonious system of representation. This closer examination of the movements and vocalizations of Norwegian killer whales, combined with future work on ontogeny and transmission, will inform our understanding of whether and how culture plays a role in achieving population-specific behaviors in this species.Funding sources: The Ocean Life Institute at WHOI and the National Geographic Society, the National Defense Science and Engineering Graduate Fellowship, a National Science Foundation Graduate Fellowship, the Academic Programs Office at WHOI and Dennis McLaughlin at MIT

A versatile pitch tracking algorithm : from human speech to killer whale vocalizations

Author Posting. © Acoustical Society of America, 2009. This article is posted here by permission of Acoustical Society of America for personal use, not for redistribution. The definitive version was published in Journal of the Acoustical Society of America 126 (2009): 451-459, doi:10.1121/1.3132525.In this article, a pitch tracking algorithm [named discrete logarithmic Fourier transformation-pitch detection algorithm (DLFT-PDA)], originally designed for human telephone speech, was modified for killer whale vocalizations. The multiple frequency components of some of these vocalizations demand a spectral (rather than temporal) approach to pitch tracking. The DLFT-PDA algorithm derives reliable estimations of pitch and the temporal change of pitch from the harmonic structure of the vocal signal. Scores from both estimations are combined in a dynamic programming search to find a smooth pitch track. The algorithm is capable of tracking killer whale calls that contain simultaneous low and high frequency components and compares favorably across most signal to noise ratio ranges to the peak-picking and sidewinder algorithms that have been used for tracking killer whale vocalizations previously.C.W. was supported by DARPA under Contract No. N66001-96-C-8526, monitored through Naval Command, Control, and Ocean Surveillance Center and by the National Science Foundation under Grant No. IRI-9618731. A.D.S. was supported by a National Defense Science and Engineering Graduate Fellowship

Movement and vocal behavior of free-ranging Norwegian killer whales (Orcinus orca)

Thesis (Ph. D.)--Joint Program in Oceanography/Applied Ocean Science and Engineering (Massachusetts Institute of Technology, Dept. of Biology; and the Woods Hole Oceanographic Institution), 2008.Includes bibliographical references.Studying the social and cultural transmission of behavior among animals helps to identify patterns of interaction and information content flowing between individuals. Killer whales are likely to acquire traits culturally based on their population-specific feeding behaviors and group-distinctive vocal repertoires. I used digital tags to explore the contributions of individual Norwegian killer whales to group carousel feeding and the relationships between vocal and non-vocal activity. Periods of tail slapping to incapacitate herring during feeding were characterized by elevated movement variability, heightened vocal activity and call types containing additional orientation cues. Tail slaps produced by tagged animals were identified using a rapid pitch change and occurred primarily within 20m of the surface. Two simultaneously tagged animals maneuvered similarly when tail slapping within 60s of one another, indicating that the position and composition of the herring ball influenced their behavior. Two types of behavioral sequence preceding the tight circling of carousel feeding were apparent. First, the animals engaged in periods of directional swimming. They were silent in 2 of 3 instances, suggesting they may have located other foraging groups by eavesdropping. Second, tagged animals made broad horizontal loops as they dove in a manner consistent with corralling. All 4 of these occasions were accompanied by vocal activity, indicating that this and tail slapping may benefit from social communication. No significant relationship between the call types and the actual movement measurements was found. Killer whale vocalizations traditionally have been classified into discrete call types. Using human speech processing techniques, I considered that calls are alternatively comprised of shared segments that can be recombined to form the stereotyped and variable repertoire.(cont.) In a classification experiment, the characterization of calls using the whole call, a set of unshared segments, or a set of shared segments yielded equivalent performance. The shared segments required less information to parse the same vocalizations, suggesting a more parsimonious system of representation. This closer examination of the movements and vocalizations of Norwegian killer whales, combined with future work on ontogeny and transmission, will inform our understanding of whether and how culture plays a role in achieving population-specific behaviors in this species.by Ari Daniel Shapiro.Ph.D

Speech Breathing in Virtual Humans: An Interactive Model and Empirical Study

Human speech production requires the dynamic regulation of air through the vocal system. While virtual character systems commonly are capable of speech output, they rarely take breathing during speaking - speech breathing - into account. We believe that integrating dynamic speech breathing systems in virtual characters can significantly contribute to augmenting their realism. Here, we present a novel control architecture aimed at generating speech breathing in virtual characters. This architecture is informed by behavioral, linguistic and anatomical knowledge of human speech breathing. Based on textual input and controlled by a set of low-and high-level parameters, the system produces dynamic signals in real-time that control the virtual character's anatomy (thorax, abdomen, head, nostrils, and mouth) and sound production (speech and breathing). In addition, we perform a study to determine the effects of including breathing-motivated speech movements, such as head tilts and chest expansions during dialogue on a virtual character, as well as breathing sounds. This study includes speech that is generated both from a text-to-speech engine as well as from recorded voice

Understanding the Predictability of Gesture Parameters from Speech and their Perceptual Importance

Gesture behavior is a natural part of human conversation. Much work has focused on removing the need for tedious hand-animation to create embodied conversational agents by designing speech-driven gesture generators. However, these generators often work in a black-box manner, assuming a general relationship between input speech and output motion. As their success remains limited, we investigate in more detail how speech may relate to different aspects of gesture motion. We determine a number of parameters characterizing gesture, such as speed and gesture size, and explore their relationship to the speech signal in a two-fold manner. First, we train multiple recurrent networks to predict the gesture parameters from speech to understand how well gesture attributes can be modeled from speech alone. We find that gesture parameters can be partially predicted from speech, and some parameters, such as path length, being predicted more accurately than others, like velocity. Second, we design a perceptual study to assess the importance of each gesture parameter for producing motion that people perceive as appropriate for the speech. Results show that a degradation in any parameter was viewed negatively, but some changes, such as hand shape, are more impactful than others. A video summarization can be found at https://youtu.be/aw6-_5kmLjY.Comment: To be published in the Proceedings of the 20th ACM International Conference on Intelligent Virtual Agents (IVA 20

The Role and Responsibility of Traditional Media

When high profile legal issues arise, the traditional media attempts a familiar balancing act, weighing ethical obligations of fairness, accuracy and objectivity against the necessity for timely and competitive reporting. This mission, in itself, requires careful execution. But there is significantly more pressure in recent years, due to a voracious 24-hour news cycle, competition by new media entities that have high-tech speed and occasionally choose to remain unfettered by journalistic ethics, and challenging economic realities. In Panel #1: The Role and Responsibility of Traditional Media, moderator Sara Beale, the Charles L. B. Lowndes Professor of Law at Duke University School of Law, talks with a panel of veteran reporters, journalism academics, and experts in the legal side of journalism. The far-ranging discussion covers the basic tenets of journalistic ethics, famous journalistic controversies, and the difficulties faced by print reporters who increasingly have to cover more ground with fewer resources. Questions/themes/discussion topics Balancing speed and accuracy The effect of smaller newsrooms and fewer reporters, especially in the world of print journalism Resisting manipulation by sources Media criticism, from ombudsmen to bloggers Historically bad journalism, from McCarthyism to Jayson Blai