The Florida State University Statistics Department

The kinematics of prey capture by the chamaeleonid lizard Chamaeleo oustaleti were studied using high-speed cinematography. Three feeding sequences from each of two individuals were analyzed for strike distances of 20 and 35 cm, at 30°C. Ten distances and angles were measured from sequential frames beginning approximately 0.5 s prior to tongue projection and continuing for about 1.0 s. Sixteen additional variables, documenting maximum excursions and the timing of events, were calculated from the kinematic profiles. Quantified descriptions of head, hyoid and tongue movements are presented. Previously unrecognized rapid protraction of the hyobranchial skeleton simultaneously with the onset of tongue projection was documented and it is proposed that this assists the accelerator muscle in powering tongue projection. Acceleration of the tongue occurred in about 20ms, reaching a maximum acceleration of 486 m s−2 and maximum velocity of 5.8m s−1 in 35 cm strikes. Deceleration of the tongue usually began within 5 ms before prey contract and the direction of tongue movement was reversed within 10 ms of prey contact. Retraction of the tongue, caused by shortening of the retractor muscles, reached a maximum velocity of 2.99 ms−1 and was complete 330 ms after prey contact. Projection distance influences many aspects of prey capture kinematics, particularly projection time, tongue retraction time and the extent of gape and head movements during tongue retraction, all of which are smaller in shorter feedings. Though several features of the chameleon strike have apparently been retained from lizards not capable of ballistic tongue projection, key differences are documented. Unlike members of a related family, the Agamidae, C. oustaleti uses no body lunge during prey capture, exhibits gape reduction during tongue projection and strongly depresses the head and jaws during tongue retraction. Note: Present address: Department of Biological Sciences, Florida State University, Tallahassee, FL 32306, USA.

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Library Express Delivery Service: The Evolution of a Campus Delivery Service at Florida State University

Journal of Interlibrary Loan Document Delivery & Electronic Reserve ◽

10.1080/1072303x.2014.895792 ◽

2013 ◽

Vol 23 (4-5) ◽

pp. 201-212 ◽

Cited By ~ 3

Author(s):

Dan Schoonover ◽

Mike Siriwardena ◽

Reginald Jones

Keyword(s):

Florida State University ◽

State University ◽

Delivery Service ◽

Express Delivery

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Shapes of Educational Data in an Online Calculus Course

Journal of Learning Analytics ◽

10.18608/jla.2017.42.8 ◽

2017 ◽

Vol 4 (2) ◽

Cited By ~ 1

Author(s):

Olga Caprotti

Keyword(s):

Markov Chain ◽

Sequence Analysis ◽

Information Space ◽

Learning Resources ◽

Florida State University ◽

State University ◽

Student Progress

This paper describes investigations in visualizing logpaths of students in an online calculus course held at Florida State University in 2014. The clickstreams making up the logpaths can be used to visualize student progress in the information space of a course as a graph. We consider the graded activities as nodes of the graph, while information extracted from the logpaths between the graded activities label the edges of the graph. We show that this graph is associated to a Markov Chain in which the states are the graded activities and the weight of the edge is proportional to the probability of that transition. When we visualize such a graph, it becomes apparent that most students follow the course sequentially, section after section. This model allows us to study how different groups of students employ the learning resources using sequence analysis on information buried in their clickstreams.

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