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Figure 3. A–G in A revision of the Australian fossil species of Zoila (Gastropoda: Cypraeidae)

Figure 3. A–G, Cypraeorbis ventripotens Moodys Branch Formation, late Eocene, Town Creek, Jackson, Mississippi, United States of America; A–C, × 2; F, × 4; D–E, G, × 2; H–J, N, Cypraeorbis arlettae MNHN, Chipola Formation, Burdigalian, early Miocene, Farley Creek, Calhoun County, Florida, USA; K, O, Cypraeorbis wilcoxi MNHN, Chipola Formation, Burdigalian, early Miocene, Farley Creek, Calhoun County, Florida, United States of America; L–M, Barycypraea zietsmani Liltved and Le Roux, 1988, P31664, Alexandria Formation, late Neogene, Eastern Cape, South Africa, × 1.

Figure 2. Protoconchs. A in A revision of the Australian fossil species of Zoila (Gastropoda: Cypraeidae)

Figure 2. Protoconchs. A, Zoila platypyga (McCoy, 1876), P308781, × 7; B, Zoila gigas (McCoy, 1867), P308792, × 3.6; C, Zoila viathomsoni sp. nov., WAM × 10.

Figure 11. A–H in A revision of the Australian fossil species of Zoila (Gastropoda: Cypraeidae)

Figure 11. A–H, Zoila platypyga; A–B, D, H, holotype, P12137, Mount Eliza, × 1; C, E, holotype of Cypraea consobrina McCoy, P12134, Mooroobool River, × 1; F–G, holotype of Cypraea toxorhyncha Tate, SAM T 823, Muddy Creek, × 1.

Figure 6. A–E, I in A revision of the Australian fossil species of Zoila (Gastropoda: Cypraeidae)

Figure 6. A–E, I, Zoila didymorhyncha; A–C, paratype, P302685, PL3022, × 1; D–E, I, holotype, P302687, PL 3022, × 1; F–H, Z. glomerabilis, paratype, P315526, Half Moon Bay, Torquay, × 1.

Figure 14. A–H in A revision of the Australian fossil species of Zoila (Gastropoda: Cypraeidae)

Figure 14. A–H, Zoila gigas; A–B, holotype of Cypraea gabrieli Chapman, P12366, Bird Rock cliffs, Torquay, × 0.5; C–E, P308679, Bird Rock cliffs, × 0.5; F–H, P13060, Grices Creek, 0.5.

Figure 13. A–C in A revision of the Australian fossil species of Zoila (Gastropoda: Cypraeidae)

Figure 13. A–C, Zoila platypyga, P304415, PL 3078, × 1; E–H, Z. gigas; E, protoconch, P308804, Muddy Creek, × 2.5; F, protoconch, P308807, Batesford Quarry, × 2; G–H, holotype of Cypraea dorsata Tate, SAM T849, Muddy Creek, × 1.

Figure 5. A, D–G, I–K in A revision of the Australian fossil species of Zoila (Gastropoda: Cypraeidae)

Figure 5. A, D–G, I–K, Zoila chathamensis; A, E, I, holotype, AIM 71325, Flower Pot Harbour, Chatham Islands; A, E, × 1.5; I, × 2; D, F–G, J–K, GNS TM8792, Taruwhenua Peninsula, Chatham Islands; D, F–G, K, × 1.5; J, × 2; B–C, H, L, Z. viathomsoni; B–C, H, holotype, WAM 72.296, Thomson Highway, Western Australia; L, fossula, P310194, Thomson Highway, × 3.

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Testing alternative hypotheses for the decline of cichlid fish in Lake Victoria using fish fossils time series from sediment cores

Lake Victoria is well known for its high diversity of endemic fish species that provide livelihoods for millions of people. The lake garnered widespread attention during the twentieth century as major environmental and ecological changes modified the fish community with the extinction of ~40% of endemic cichlid species by the 1980s. Suggested causal factors include anthropogenic eutrophication, fishing, and introduced non-native species but their relative importance remains unresolved because monitoring data started in the 1970s when changes were already underway. Here, for the first time, we reconstruct two time series, covering the last ~200 years, of fish assemblage using fish teeth preserved in lake sediments. Two sediment cores Lake Victoria (Mwanza Gulf), were subsampled continuously at intra-decadal resolution, and teeth were identified to major taxa: Cyprinoidea, Haplochromini, Mochokidae, and Oreochromini. None of the fossils could be confidently assigned to non-native Nile Perch. Our data show significant decreases in haplochromine and oreochromine cichlid fish abundances began long before Nile Perch's arrival, while cyprinoids have generally been increasing. Our study is the first to reconstruct a time series of fish assemblage in Lake Victoria extending deeper back in time than the past 50 years, helping shed light on processes underlying Lake Victoria's biodiversity loss.

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Data from: Inferring the evolution of reproductive isolation in a lineage of fossil threespine stickleback, Gasterosteus doryssus

Darwin attributed the absence of species transitions in the fossil record to his hypothesis that speciation occurs within isolated habitat patches too geographically restricted to be captured by fossil sequences. Mayr's peripatric speciation model added that such speciation would be rapid, further explaining missing evidence of diversification. Indeed, Eldredge and Gould's original punctuated equilibrium model combined Darwin's conjecture, Mayr's model, and 124 years of unsuccessfully sampling the fossil record for transitions. Observing such divergence, however, could illustrate the tempo and mode of evolution during early speciation. Here, we investigate peripatric divergence in a Miocene stickleback fish, Gasterosteus doryssus. This lineage appeared and, over ~8,000 generations, evolved significant reduction of twelve of sixteen traits related to armor, swimming, and diet, relative to its ancestral population. This was greater morphological divergence than we observed between reproductively isolated, benthic-limnetic ecotypes of extant Gasterosteus aculeatus. Therefore, we infer that reproductive isolation was evolving. However, local extinction of low-armoured G. doryssus lineages shows how young isolate populations often disappear, supporting Darwin's explanation for missing evidence and revealing a mechanism behind morphological stasis. Exctinction may also account for limited sustained divergence within the stickleback species complex and help reconcile speciation rate variation observed across time scales.

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Figure 25 in Identification of fossil worm tubes from Phanerozoic hydrothermal vents and cold seeps

Figure 25. Results of confocal laser-scanning microscopy (CLSM) of recently mineralized and ancient fossil annelid tubes (see online edition for colour version). Tubes are imaged in auto-fluorescence mode, where areas of fluorescence likely reflect the presence of organic matter. A, detail of mineralized Escarpia southwardae (Siboglinidae) tube transverse section. B, fossil tube from Upper Waiau River, New Zealand (UWT3-4), detail of transverse section. C, fossil tube from West Fork Satsop River, Washington State, USA (WFSR 1A), detail of transverse section. D, fossil tubes from Bexhaven, New Zealand (BXG), detail of two near-transverse sections. Scale bars: A = 100 µm; B–D = 200 µm.

Figure 24 in Identification of fossil worm tubes from Phanerozoic hydrothermal vents and cold seeps

Figure 24. Fourier transform infrared (FTIR) spectroscopy spectra of the organic tubes of vent and seep annelids. Spectra are offset on the absorbance axis, and key spectral absorbance peaks are labelled with the types of chemical bonds they represent: -NH, nitrogenhydrogen; -CH, carbon-hydrogen; -OH, oxygen-hydrogen. The regions of the tube analysed are as follows: Tevnia jerichonana (anterior, inner tube wall); Zenkevitchiana longissimi (middle, outer tube wall); Lamellibrachia anaximandri (posterior, outer tube wall); Sclerolinum contortum (anterior, outer tube wall); Alvinella sp. (middle); Spiochaetopterus izuensis (middle, outer tube wall).

Figure 23. Strict consensus cladograms constructed using a in Identification of fossil worm tubes from Phanerozoic hydrothermal vents and cold seeps

Figure 23. Strict consensus cladograms constructed using a total of 64 modern and fossil annelid taxa and 48 mostly morphological tube characters. Analyses were performed using implied character weighting, with the concavity constant set as default (k = 3; A), and also set to downweight homoplastic characters less (k = 4; B). Numbers on nodes represent groups present/contradicted support values. Modern taxa are coloured according to taxonomic groups; fossil taxa are in grey. A, consensus of 271 most parsimonious trees (best score = 15.387, consistency index = 0.195, retention index = 0.264); B, consensus of 60 most parsimonious trees (best score = 13.568, consistency index = 0.232, retention index = 0.569). Symbols/colours indicate taxonomic affinities.

Figure 21 in Identification of fossil worm tubes from Phanerozoic hydrothermal vents and cold seeps

Figure 21. Principal coordinate analysis plot of modern and fossil annelid tubes, based on the 48 characters scored for this study. Fossils (grey crosses): 1. Yamankasia rifeia; 2, Eoalvinellodes annulatus; 3, 'Sibay tubes'; 4, Tevidestus serriformis; 5, 'Figueroa tubes'; 6, 'Sassenfjorden area tubes'; 7, 'Cold Fork Cottonwood Creek tubes'; 8, 'Prince Patrick tubes'; 9, 'Ellef Ringnes tubes'; 10, 'Troodos attached tubes'; 11, 'Troodos wrinkled tubes'; 12, 'Troodos collared tubes'; 13, 'Okukinenbetsu yellow tubes'; 14, 'Okukinenbetsu brown tubes'; 15, 'Omagari tubes'; 16, 'Canyon River tubes'; 17, 'Murdock Creek tubes'; 18, 'West Fork Satsop River tubes'; 19, Serpulidae sp., 'Bexhaven'; 20, 'Upper Waiau River tubes'; 21, 'Rocky Knob tubes'. Modern tubes: Chaetopteridae (orange dots): 22, Chaetopterus cf. variopedatus; 23, Chaetopteridae id83; 24, Phyllochaetopterus polus; 25, P. gigas; 26, P. claparedii; 27, P. prolifica; 28, P. socialis; 29, Spiochetopterus izuensis; 30, S. sagamiensis; 31, S. costarum; 32, S. typicus; 33, Mesochaetopterus taylori. Siboglinidae, frenulata (dark blue filled triangles): 34, Galathealinum arcticum; 35, Lamellisabella denticulata; 36, Oligobrachia gracilis; 37, Polybrachia canadensis; 38, Siboglinum ekmani; 39, S. lacteum; 40, Siphonobrachia lauensis; 41, Unibrachium colombianum; 42, Zenkevitchiana longissima; 43. Siboglinidae, Sclerolinum (light blue outline triangle): S. contortum; Siboglinidae, vestimentiferans (light purple filled inverted triangles): 44, Alaysia spiralis; 45, Arcovestia ivanovi; 46, Escarpia southwardae; 47, Lamellibrachia anaximandri; 48, Paraescarpia echinospica; 49, Ridgeia piscesae; 50, Riftia pachyptila; 51, Tevnia jerichonana; 52, Seepiophila jonesi; Siboglinidae, vestimentiferan roots (dark purple outline inverted triangles): 53, E. southwardae root; 54, L. anaximandri root; 55, S. jonesi root; 56, P. echinospica root; Alvinellidae (maroon outline diamond): 57, Alvinella sp.; Ampharetidae (fuchsia outline rhombus): 58, Glyphanostomum sp.; Serpulidae (lime filled squares): 59, Serpulidae sp. JCR; 60, Serpula vermicularis; 61, Vermiliopsis infundibulum; Sabellidae (yellow outline squares): 62, Sabella pavonina; 63, Megalomma vesiculosum; Oweniidae (dark green outline dot): 64. Owenia fusiformis.

Figure 19 in Identification of fossil worm tubes from Phanerozoic hydrothermal vents and cold seeps

Figure 19. Yamankasia rifeia, Silurian, Yaman Kasy, Russia. A, NHMUK VF84, large tube in hand specimen. B, NHMUK VF97, cast of tube exhibiting fold. C, NHMUK VF78, pyritized fibres or filamentous micro-organisms preserved on the outside of a tube. D, NHMUK VF78, fine longitudinal wrinkles preserved on outer tube surface. E, NHMUK OR6468a, tube in transverse section with thick, multi-layered wall. F, NHMUK OR6468b, tube wall in transverse section preserved as several layers. G, UL 61633, detail of tube transverse section showing colloform pyrite interpreted as having grown on the outside of the tube. Scale bars: A = 10 mm; B = 5 mm; C = 500 µm; D = 3 mm; E = 1.5 mm; F, G = 500 µm.

Figure 22 in Identification of fossil worm tubes from Phanerozoic hydrothermal vents and cold seeps

Figure 22. Strict consensus cladogram of the three most parsimonious trees of tubes built by a total of 43 modern annelid taxa (best score = 14.344, consistency index = 0.308, retention index = 0.629). The analysis was based on the 48 mostly morphological tube characters and was performed using implied character weighting (k = 3). Numbers on nodes represent groups present/contradicted support values. Symbols/colours indicate taxonomic affinities.

Figure 18 in Identification of fossil worm tubes from Phanerozoic hydrothermal vents and cold seeps

Figure 18. Eoalvinellodes annulatus, Silurian, Yaman Kasy, Russia. A–C, NHMUK OR1388a, NHMUK VF52 and NHMUK VF53, respectively, hand specimens of gently curving tubes with folded fabric-like tube wall texture. D, E, UL YKB1, transverse sections of tubes showing thick walls with thick, possibly multi-layered walls. F, UL YKB1, detail of tube wall in transverse section showing preservation by colloform pyrite many layers thick. Scale bars: A, B = 2 mm; C = 1 mm; D, E = 500 µm; F = 100 µm.

Figure 16. A–C in Identification of fossil worm tubes from Phanerozoic hydrothermal vents and cold seeps

Figure 16. A–C, Tevidestus serriformis tubes, Devonian, Sibay, Russia, NHMUK VF71; A, tube fragment exhibiting numerous short collars; B, C, detail of tube wall showing small collars and meshwork of fibres. D, Phyllochaetopterus prolifica outer tube wall detail for comparison, NHMUK 1915.5.1.4-6. Scale bars: A = 4 mm; B, C = 1 mm; D = 10 µm.

Figure 17 in Identification of fossil worm tubes from Phanerozoic hydrothermal vents and cold seeps

Figure 17. 'Sibay tubes', NHMUK VF71, Devonian, Sibay, Russia. A, hand specimen showing cluster of tubes in various orientations. B, detail of tube wall showing smooth appearance. C, detail of the walls of three adjacent tubes in transverse section; walls appear thick and multi-layered. D, detail of framboidal pyrite preserving tube walls. Scale bars: A = 3 mm; B = 1 mm; C = 500 µm; D = 10 µm.

Figure 14 in Identification of fossil worm tubes from Phanerozoic hydrothermal vents and cold seeps

Figure 14. 'Sassenfjorden area tubes', Volgian–Ryazanian, Svalbard. A–C, hand specimens of tubes; A, Svalbard 2007-03, long tube with poorly preserved walls; B, PMO 2009-01, smooth-walled tube possibly with a small collar; C, PMO 2009-03, tube with possible longitudinal wrinkles. D, E, 171.002D, near-transverse sections of tubes with thick, neatly-multi-layered walls. F, 170.996, detail from transverse section of a tube where the tube exhibits curving layers that have separated. G, 171.027, tube with poorly preserved walls. Scale bars: A = 10 mm; B = 2 mm; C = 5 mm; D, E = 300 µm; F = 100 µm; G = 200 µm.

Figure 13 in Identification of fossil worm tubes from Phanerozoic hydrothermal vents and cold seeps

Figure 13. 'Wilbur Springs tubes', WS-45, Hauterivian, California, USA. A, smooth-walled, tapering tube in hand specimen. B, transverse section of tube with replaced wall that may have been originally calcareous in composition. C–E, tube walls in near-transverse section with poorly preserved walls that may have originally been organic in composition. Scale bars: A = 10 mm; B = 500 µm; C, E = 200 µm; D = 400 µm.