Morphometric analysis of lungfish endocasts elucidates early dipnoan palaeoneurological evolution
Figures
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Endocast of Griphognathus whitei (NHMUK PV P56054) in (a), dorsal; (b, c), lateral; (d), ventral views.
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Endocast of Iowadipterus halli (FMNH PF 12323) in (a), dorsal; (b), lateral left; (c), lateral right; and (d), ventral views.
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Endocast of Orlovichthys limnatis (PIN 3725/110) in (a), dorsal; (b), lateral left; (c), lateral right; and (d), ventral views.
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Endocast of Pillararhynchus longi (ANU 49196) in (a), dorsal; (b), lateral left; (c), lateral right; and (d), ventral views.
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Endocast of Gogodipterus paddyensis (WAM 70.4.250) labyrinth region in (a), dorsal; and (b), right lateral views with transparent skull overlay; (c), dorsal; (d), right lateral; (e), anterior; (f), posterior views of labyrinth endocast only.
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Endocast of Rhinodipterus ulrichi (NRM P6609a) in (a), dorsal; (b), lateral left; (c), lateral right; and (d), ventral views.
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Illustration of 17 endocast variables measured on endocast in (a), dorsal; (b), left lateral; and (c), ventral view.
ANG_OLF, angle of bifurcation between olfactory canals; D_NII, depth of cranial endocast at level of n.II; D_NV, depth of cranial endocast at level of n.V; DEP_HYP_F, depth of cranial endocast at level of hypophyseal fossa; HF_NII, distance from hypophyseal fossa to n.II; NAS_CAP_L, length of nasal capsules; NII_ OLF_BIF, distance from n.II to point of bifurcation between olfactory canals; NV_HF, distance from n.V to hypophyseal fossa; NX_NV, distance from n.V to n.X; OLF_CAN_L, length of olfactory canals from nasal capsules to point of bifurcation; SAC_H, height of sacculus; SAC_L, length of sacculus; SCC_H, height of semicircular canals; SCC_L, length of semicircular canals from anterior to posterior; SCC_W, width of semicircular canals from midline to lateral canal; UTR_H, height of utriculus; UTR_L, length of utriculus.
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Standard Principal Component Analysis (PCA) biplot of lungfish endocast shape optimised for maximum number of included TAXA, PC1 vs PC2.
Loadings and eigenvalues shown in Figure 8—figure supplement 1.
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Standard Principal Component Analysis (PCA) biplot of lungfish endocast shape optimised for maximum number of included CHARACTERS.
(A), PC1 vs PC2; (B), PC1 vs PC3; (C), PC2 vs PC3. Loadings and eigenvalues shown in Figure 9—figure supplements 1 and 2.
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Standard PCA loadings optimised for CHARACTERS A, PC1; B, PC2; and C, PC3.
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Standard PCA eigenvalues optimised for maximum A, CHARACTERS; and B, TAXA.
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Bayesian Principle Component Analysis (BPCA) biplot of lungfish endocast shape (A), PC 1 vs PC 2 with endocasts of select taxa shown; and (B), (C) loadings for PCA 1–2.
Eigenvalues shown in Figure 10—figure supplement 1.
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PCA eigenvalues for A, Bayesian Principle Component Analysis (BPCA); and B, Principle Component Analysis for incomplete data (InDaPCA).
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Principle Component Analysis for incomplete data (InDaPCA) biplot of lungfish endocast shape for (A), PC1 vs PC2; (B), PC1 vs PC3; (C), PC2 vs PC3, with endocasts of select taxa shown.
Explanation of variable abbreviations as per Figure 7.
![](https://iiif.elifesciences.org/lax/73461%2Felife-73461-fig11-figsupp1-v1.tif/full/617,/0/default.jpg)
Principle Component Analysis for incomplete data (InDaPCA) loadings for A, PC1; B, PC2; and C, PC3.
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Palaeozoic lungfish endocasts in dorsal, ventral, and left lateral views, placed onto phylogeny adapted from Challands et al., 2019 .
*The following endocasts were first published elsewhere but new images were created for inclusion in this figure: Rhinodipterus kimberleyensis (Clement and Ahlberg, 2014) Figures 2 and 3; Dipterus valenciennesi (Challands, 2015) Figures 6 and 9; ‘Chirodipterus’ australis (Henderson and Challands, 2018) Figures 3–4; Dipnorhynchus sussmilchi (Clement et al., 2016a) Figures 2—4.
Additional files
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Transparent reporting form
- https://cdn.elifesciences.org/articles/73461/elife-73461-transrepform1-v1.pdf
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Source data 1
Table containing endocast measurements as a matrix, including additional comments and variables.
- https://cdn.elifesciences.org/articles/73461/elife-73461-data1-v1.xlsx
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Source data 2
Table containing PCA loadings for the taxa-optimised analyses.
- https://cdn.elifesciences.org/articles/73461/elife-73461-data2-v1.xlsx
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Source data 3
Table containing PCA loadings for the character-optimised analyses.
- https://cdn.elifesciences.org/articles/73461/elife-73461-data3-v1.xlsx
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Source data 4
Table containing loadings for the BPCA.
- https://cdn.elifesciences.org/articles/73461/elife-73461-data4-v1.xlsx
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Source data 5
Table containing loadings for the InDaPCA.
- https://cdn.elifesciences.org/articles/73461/elife-73461-data5-v1.xlsx