Amplitude modulation in sound signals by mammals

Periodic variations in amplitude of a signal, or amplitude modulation (AM), affect the structure of communicative messages spectrum. Within the spectrum of AM-signals, side frequencies are formed both above and below the carrier frequency that is subjected to modulation. In case of harmonic signal structure they are presented near fundamental frequency as well as near harmonics. Thus, AM may by viewed as a relatively simple mechanism for controlling the spectrum of messages transmitted by mammals. Examples of AM affecting the spectrum structure of functionally different sound signals are discussed as applied to representatives of four orders of mammals: rodents (Reodentia), duplicidentates (Lagomorpha), pinnipeds (Pinnipedia), and paridigitates (Artiodactia). For the first time, the classification of AM in animals' sound signals is given. Five forms of AM are picked out in sound signals by mammals: absence of AM, continuous AM, fragmented, heterogeneous, and multilevel one. AM presence/absence is related neither with belonging to any specific order nor with some particular function of a signal. Similar forms of AM can occur in different orders of mammals in parallel. On the contrary, different forms of AM can be detected in signals meant for similar functions. The assumption is made about AM-signals facilitating information encoding and jamprotection of messages transmitted by mammals. Preliminry analysis indicates that hard-driving amplitude modulation is incompatible with hard-driving frequency modulation.

Авторы
Редакторы
-
Издательство
-
Номер выпуска
3
Язык
Русский
Страницы
225-240
Статус
Опубликовано
Подразделение
-
DOI
-
Номер
-
Том
73
Год
2012
Организации
  • 1 Russian University of Peoples Friendship, Ecological Faculty, Pavlovskaya, 8/5, 113093 Moscow, Russian Federation
Ключевые слова
animal; article; Artiodactyla; classification; hearing; lagomorph; oscillometry; physiology; rodent; seal; sound detection; vocalization; Animals; Artiodactyla; Auditory Perception; Lagomorpha; Oscillometry; Pinnipedia; Rodentia; Sound Spectrography; Vocalization, Animal; Animalia; Lagomorpha; Mammalia; Pinnipedia; Rodentia
Дата создания
19.10.2018
Дата изменения
19.10.2018
Постоянная ссылка
https://repository.rudn.ru/ru/records/article/record/2288/