01634nas a2200109 4500008004100000245012700041210006900168520107300237100001901310700001301329856018201342 2004 eng d00aAutomated identification of field-recorded songs of four British grasshoppers using bioacoustic signal recognitionAbstract0 aAutomated identification of fieldrecorded songs of four British 3 a

Recognition of Orthoptera species by means of their song is widely used in field work but requires expertise. It is now possible to develop computer-based systems to achieve the same task with a number of advantages including continuous long term unattended operation and automatic species logging. The system described here achieves automated discrimination between different species by utilizing a novel time domain signal coding technique and an artificial neural network. The system has previously been shown to recognize 25 species of British Orthoptera with 99% accuracy for good quality sounds. This paper tests the system on field recordings of four species of grasshopper in northern England in 2002 and shows that it is capable of not only correctly recognizing the target species under a range of acoustic conditions but also of recognizing other sounds such as birds and man-made sounds. Recognition accuracies for the four species of typically 70–100% are obtained for field recordings with varying sound intensities and background signals.

1 aChesmore, E.D.1 aOhya, E. uhttps://www.cambridge.org/core/product/identifier/S0007485304000331/type/journal_articlehttps://www.cambridge.org/core/services/aop-cambridge-core/content/view/S000748530400033100433nas a2200109 4500008004100000245007300041210006900114300001400183490000700197100002100204856009800225 1952 eng d00aEcological studies on solitary Acrididae in England and South Africa0 aEcological studies on solitary Acrididae in England and South Af a165–2030 v151 aChapman, Kenneth uhttps://bio.acousti.ca/content/ecological-studies-solitary-acrididae-england-and-south-africa03469nas a2200145 4500008004100000022001300041245012300054210006900177260001600246300001200262490000600274520295200280100002603232856006503258 1958 eng d a0003347200aStridulation and associated behaviour in certain orthoptera. 2. Stridulation of females and their behaviour with males0 aStridulation and associated behaviour in certain orthoptera 2 St cJan-01-1958 a27 - 420 v63 a

1. The stridulation of females and their behaviour in relation to males was studied comparatively in the following species of Truxalinae: Stenobothrus lineatus (Panzer); Omocestus viridulus (Linnaeus); Chorthippus parallelus (Zetterstedt); and Chorthippus brunneus (Thunberg) (= C. bicolor Charp.).

2. Descriptions of the “typical behaviour” of females in response to normal song are given. This behaviour is similar in all species and consists of three phases: response stridulation, orientation towards and locomotion to the male. Arrived near the male, the female stridulates in response to mate song; the male, on noticing the female, sings the courtship song, engages the genitalia and copulation ensues. Females showing such typical behaviour are said to be in the “responsive state”.

3. This responsive state in females of the four species appears at maturation, is inhibited for periods up to 24 hours prior to oviposition, is regained shortly afterwards and is lost some days prior to death. Complete copulation involving the transfer of a spermatophore also inhibits the responsive state in the females; if the latter are isolated after copulation, they regain their responsiveness in a period of from 6–20 days dependent on the species. This recovery is delayed or prevented if the females are kept after copulation with males or within the sound of male normal song.

4. The responsive state is characterised in most females of all four species by the emission of stridulation in response to male normal song. In all cases, the movements of the hind femora of a female emitting this stridulation are very similar to those of a male of the same species singing the normal song. In the case of S. lineatus, O. viridulus and C. brunneus, audible sounds are emitted by the females, which in the case of the latter two species show marked affinity to male normal song. Physical analyses of these sounds are presented. Females of C. parallelus, being brachypterous, emit no sound while making stridulation movements of the hind femora.

5. It is postulated that the discrimination mechanism responsible for distinguishing between various specific songs is closely linked to the inherited motor mechanism which causes typical stridulation in both sexes. It is further suggested that the basic behaviour reactions of males and females to male normal song are the same, consisting of stridulation response movements, orientation and locomotion towards the male. Normally in the field, the last two phases are suppressed in males, the whole sequence in females. Isolation restores full typical behaviour in both males and females and, in the latter, stridulation is always an indicator of the return of the responsive state.

6. The observations are used to construct a possible picture of events in the field concerned with courtship and mating in the present species.

1 aHaskell, Peter Thomas uhttp://linkinghub.elsevier.com/retrieve/pii/000334725890005801712nas a2200157 4500008004100000022001400041245010200055210006900157260001600226300001300242490000800255520120200263100001701465700002401482856004801506 1987 eng d a0340-759400aSeparate localization of sound recognizing and sound producing neural mechanisms in a grasshopper0 aSeparate localization of sound recognizing and sound producing n cJan-01-1987 a95 - 1010 v1613 a

In the two acridid species Chorthippus parallelus and Ch. montanus, the sound template by which females recognize male song varies with temperature, as does the song itself. At relatively high temperatures the females respond best to simulated songs with high syllable frequencies, and at lower temperatures songs with lower syllable frequencies are preferred.

The temperature around the supraesophageal and metathoracic ganglia of female grasshoppers was monitored by implanted thermocouples, and either the head or the thorax was warmed selectively while the animal was free to move (within the imits of the wires). Then simulations of the conspecific song varying in syllable frequency corresponding to different song temperatures were presented, and the stridulatory responses of the animals were observed.

The results were as follows. 1. Song recognition (in particular, the position of the peak of the response curve) depended on the temperature of the head. 2. The rate of stridulatory hindleg movement was determined by the temperature of the thoracic ganglia.

This result provides strong evidence against the genetic coupling hypothesis.

1 aBauer, Maria1 avon Helversen, Otto uhttp://link.springer.com/10.1007/BF0060945802827nas a2200121 4500008004100000245010000041210006900141260004300210490000800253520230000261100002502561856011902586 1997 eng d00aIncipient Speciation In The Meadow Grasshopper, Chorthippus parallelus (Orthoptera: Acrididae).0 aIncipient Speciation In The Meadow Grasshopper Chorthippus paral aNorwich, UKbUniversity of East Anglia0 vPhD3 a

This thesis examines the evolutionary divergence between northern European and Italian populations of Chorthippus parallelus. Several differing approaches were taken, which identified the inception of various components of the speciation process between these parapatric populations which meet in the Alps.

Firstly, partial post-zygotic reproductive isolation was demonstrated using hybrid crosses. The male hybrid offspring of both reciprocal crosses were sterile, displaying severe testicular dysfunction, while the female hybrids showed no deleterious effects of hybridisation. In this grasshopper the males are the heterogametic sex, possessing a single X chromosome, and so this pattern of hybrid sterility conforms to Haldane's rule. Secondly, investigation of the calling song of the male grasshopper, a component of the mate recognition system, suggested the presence of pre-mating reproductive isolation. Males from the different races were found to sing calling song of a significantly different structure. Finally, examination of DNA sequence divergence in a mitochondrial DNA marker demonstrated Significant levels of genetic differentiation between the races. This population divergence and incipient reproductive isolation parallels that found between the north European and Iberian populations of this grasshopper, and provides further evidence that the divergent geographical races have resulted from allopatric divergence while in isolated refugial populations during the glacial periods of thePleistocene Epoch.

These approaches were repeated to investigate genetic divergence between localised populations within the Italian peninsula. No hybrid dysfunction was observed between these populations, suggesting that they are recently derived from one continuous population. This was probably the refugial population of the last ice-age. Additionally, investigation with the mtDNA marker gave preliminary evidence for population expansion from the south to the north of Italy. Interestingly, the male calling song was Significantly different in populations from the north and the south of Italy, suggesting that a component of pre-mating reproductive isolation may have evolved prior to post-mating isolation in allopatric populations of C. parallelus.

1 aFlanagan, Nicola, S. uhttps://bio.acousti.ca/content/incipient-speciation-meadow-grasshopper-chorthippus-parallelus-orthoptera-acrididae