ammonoid

(redirected from Ammonoids)
Also found in: Dictionary, Thesaurus, Medical, Wikipedia.
Related to Ammonoids: ammonite

ammonoid

[′a·mə‚nȯid]
(paleontology)
A cephalopod of the order Ammonoidea.
References in periodicals archive ?
There was little apparent difference between the geometry of the ammonoids found in the blue-gray and beige limestones (Figures 3 and 4; Tables 2 and 3).
Of the 400 ammonoids measured by the students, 319 were found in the light beige limestone (79.
The Southpark Mall, as well as numerous other public localities across the eastern United States, offers a data set of cross-sectioned ammonoids that can be used to measure shell geometry and teach functional morphology to undergraduate and high school students.
Research projects might compare the size of the ammonoids between the two types of limestone, for example.
Students found that the majority of the ammonoids present in the tile of Southpark Mall fell within the abundance contours presented in Raup (1967; Figure 5) and that there was little difference between the ammonoid geometry between the two varieties of tile.
Learning outcomes were threefold for this exercise: (1) students increased their understanding of functional morphology and growth strategy of ammonoids, especially with respect to hydrodynamic streamlining and swimming stability; (2) students compared their findings with earlier reported findings related to ammonoid coiling strategies, allowing students to both critique the earlier work and gain insights into the methods and limits of the scientific method in the historical sciences; and (3) students learned about proper specimen selection to avoid data-set contamination and sampling error.
Geometric analysis of shell coiling: coiling of ammonoids.
Sample student data sheet describing the coiling dimensions of the ammonoids from Southpark Mall.
During the Devonian Period, the ammonoid cephalopods radiated and diversified and they survived repeated episodes of mass extinction followed by rapid diversification.
Further, only the best illustrations were used for calculating ammonoid dimensions (Raup, 1967).
The underlying goal of this project was to teach students about ammonoid coiling strategies by having them measure ammonoid cross-sectional geometry and calculate the variety of coiling approaches, W and D.
Students were required to take all the following measurements for each appropriate ammonoid in their assigned floor space (a, c, d, e; Figure 2) and calculate W and D.