|
|
The Woodcock’s head: Resolving a morphological oddity using geometric morphometrics |
Jesus Marugán-Lobón |
Unidad de Paleontología, Dpto. Biología, Universidad Autonóma de Madrid, Spain; E-mail: jesus.marugan@uam.es |
|
|
Abstract The scope of shape analysis based on geometric morphometrics has evolved into underscoring complex patterns of multidimensional shape change with multivariate statistical modelling (e.g., allometry, morphological integration, etc.). Such breakthrough was made possible because the method relies on a consistent comparative reference system to compare shapes, the latter which is computed using the Cartesian coordinates of homologous landmarks. It has been shown elsewhere that traditional comparative reference systems based on anatomy, and oriented in stereotyped postures, such as the Frankfurt plane at rest, the Lateral Semicircular Canal when the animal is in alert, or the cranial floor when the animal is flying, are all inconsistent for anatomical comparisons. They vary too much and unpredictably across species. An extraordinary example of the problems that can arise in descriptive and comparative anatomy when using such reference systems is the traditional interpretation of the head of the Woodcock. Anywhere in literature it is written that the eyes of this gamebird are oriented backwards to protect itself from predators. Here, using geometric morphometrics it is demonstrated that the woodcock’s skull is highly transformed, yet following a normal trend among birds. In turn, using GM it is demonstrated that the collective wisdom about this oddity is simply the result of interpreting the anatomy of its skull using unreliable reference systems.
|
|
Fund:The work was financial supported by the Spanish MINECO, Project CGL-2013-42643. |
Corresponding Authors:
Jesus Marugán-Lobón
E-mail: jesus.marugan@uam.es
|
|
|
|
[1] |
Ming Bai. Geometric morphometrics: Current and future in China[J]. Zoological Systematics, 2017, 42(1): 1-3. |
[2] |
Norman MacLeod. Morphometrics: History, development methods and prospects[J]. Zoological Systematics, 2017, 42(1): 4-33. |
[3] |
Ming Bai, Jing Li, Wencheng Wang, Rolf G. Beutel, Benjamin Wipfler, Wangang Liu, Sha Li, Mengna Zhang, Yuanyuan Lu, Xingke Yang. A web based tool to merge geometric morphometric data from multiple characters[J]. Zoological Systematics, 2017, 42(1): 34-45. |
[4] |
Jean-Pierre Dujardin, Sebastien Dujardin, Dramane Kaba, Soledad Santillán-Guayasamin, Anita G. Villacís, Sitha Piyaselakul, Suchada Sumruayphol, Yudthana Samung, Ronald Morales Vargas. The maximum likelihood identification method applied to insect morphometric data[J]. Zoological Systematics, 2017, 42(1): 46-58. |
[5] |
Cesar Parra, Jonathan Liria. Shell geometric morphometrics in Biomphalaria glabrata (Mollusca: Planorbidae) uninfected and infected with Schistosoma mansoni[J]. Zoological Systematics, 2017, 42(1): 59-64. |
[6] |
Rongrong Li, Hufang Zhang, Shengcai Li, Ming Bai. Geometric morphometric analysis of Eysarcoris guttiger, E. annamita and E. ventralis (Hemiptera: Pentatomidae)[J]. Zoological Systematics, 2017, 42(1): 90-101. |
|
|
|
|