Publications by category
Books
Xian-Guang H, Aldridge RJ, Pei-Yun C, Siveter DJ, Siveter DJ, Gabbott SE, Xiao-Ya M, Purnell MA, Williams M (2017).
The Cambrian Fossils of Chengjiang, China the Flowering of Early Animal Life., John Wiley & Sons.
Abstract:
The Cambrian Fossils of Chengjiang, China the Flowering of Early Animal Life
Abstract.
Journal articles
Chen H, Parry L, Vinther J, Zhai D, Hou X, Ma X (In Press). A Cambrian crown annelid reconciles phylogenomics and the fossil record. Nature
Saleh F, Guenser P, Gibert C, Balseiro D, Serra F, Waisfeld BG, Antcliffe JB, Daley AC, Mángano MG, Buatois LA, et al (2022). Contrasting Early Ordovician assembly patterns highlight the complex initial stages of the Ordovician Radiation.
Sci Rep,
12(1).
Abstract:
Contrasting Early Ordovician assembly patterns highlight the complex initial stages of the Ordovician Radiation.
The Early Ordovician is a key interval for our understanding of the evolution of life on Earth as it lays at the transition between the Cambrian Explosion and the Ordovician Radiation and because the fossil record of the late Cambrian is scarce. In this study, assembly processes of Early Ordovician trilobite and echinoderm communities from the Central Anti-Atlas (Morocco), the Montagne Noire (France), and the Cordillera Oriental (Argentina) are explored. The results show that dispersal increased diachronically in trilobite communities during the Early Ordovician. Dispersal did not increase for echinoderms. Dispersal was most probably proximally triggered by the planktic revolution, the fall in seawater temperatures, changes in oceanic circulation, with an overall control by tectonic frameworks and phylogenetic constraints. The diachronous increase in dispersal within trilobite communities in the Early Ordovician highlights the complexity of ecosystem structuring during the early stages of the Ordovician Radiation. As Early Ordovician regional dispersal was followed by well-documented continental dispersal in the Middle/Late Ordovician, it is possible to consider that alongside a global increase in taxonomic richness, the Ordovician Radiation is also characterized by a gradual increase in dispersal.
Abstract.
Author URL.
Zhang G, Parry LA, Vinther J, Ma X (2022). Exceptional soft tissue preservation reveals a cnidarian affinity for a Cambrian phosphatic tubicolous enigma.
Proceedings of the Royal Society B: Biological Sciences,
289(1986).
Abstract:
Exceptional soft tissue preservation reveals a cnidarian affinity for a Cambrian phosphatic tubicolous enigma
. Exoskeletal dwelling tubes are widespread among extant animals and early fossil assemblages. Exceptional fossils from the Cambrian reveal independent origins of tube dwelling by several clades including cnidarians, lophophorates, annelids, scalidophorans, panarthropods and ambulacrarians. However, most fossil tubes lack preservation of soft parts, making it difficult to understand their affinities and evolutionary significance.
. Gangtoucunia aspera
. (Wulongqing Formation, Cambrian Stage 4) was an annulated, gradually expanding phosphatic tube, with occasional attachments of multiple, smaller juveniles and has previously been interpreted as the dwelling tube of a ‘worm’ (e.g. a scalidophoran), lophophorate or problematicum. Here, we report the first soft tissues from
. Gangtoucunia
. that reveal a smooth body with circumoral tentacles and a blind, spacious gut that is partitioned by septa. This is consistent with cnidarian polyps and phylogenetic analysis resolves
. Gangtoucunia
. as a total group medusozoan. The tube of
. Gangtoucunia
. is phenotypically similar to problematic annulated tubular fossils (e.g.
. Sphenothallus
.
. Byronia
. hyolithelminths), which have been compared to both cnidarians and annelids, and are among the oldest assemblages of skeletal fossils. The cnidarian characters of
. G. aspera
. suggest that these early tubular taxa are best interpreted as cnidarians rather than sessile bilaterians in the absence of contrary soft tissue evidence.
.
Abstract.
Ma X, Wang G, Wang M (2022). Impact of Chinese palaeontology on evolutionary research. Philosophical Transactions of the Royal Society B: Biological Sciences, 377(1847).
Saleh F, Vaucher R, Vidal M, Hariri KE, Laibl L, Daley AC, Gutiérrez-Marco JC, Candela Y, Harper DAT, Ortega-Hernández J, et al (2022). New fossil assemblages from the Early Ordovician Fezouata Biota.
Sci Rep,
12(1).
Abstract:
New fossil assemblages from the Early Ordovician Fezouata Biota.
The Fezouata Biota (Morocco) is a unique Early Ordovician fossil assemblage. The discovery of this biota revolutionized our understanding of Earth's early animal diversifications-the Cambrian Explosion and the Ordovician Radiation-by suggesting an evolutionary continuum between both events. Herein, we describe Taichoute, a new fossil locality from the Fezouata Shale. This locality extends the temporal distribution of fossil preservation from this formation into the upper Floian, while also expanding the range of depositional environments to more distal parts of the shelf. In Taichoute, most animals were transported by density flows, unlike the in-situ preservation of animals recovered in previously investigated Fezouata sites. Taichoute is dominated by three-dimensionally preserved, and heavily sclerotized fragments of large euarthropods-possibly representing nektobenthic/nektic bivalved taxa and/or hurdiid radiodonts. Resolving whether this dominance reflects a legitimate aspect of the original ecosystem or a preservational bias requires an in-depth assessment of the environmental conditions at this site. Nevertheless, Taichoute provides novel preservational and palaeontological insights during a key evolutionary transition in the history of life on Earth.
Abstract.
Author URL.
Saleh F, Ma X, Guenser P, Mángano MG, Buatois LA, Antcliffe JB (2022). Probability-based preservational variations within the early Cambrian Chengjiang biota (China).
PeerJ,
10Abstract:
Probability-based preservational variations within the early Cambrian Chengjiang biota (China).
The Chengjiang biota (Yunnan Province, China) is a treasure trove of soft-bodied animal fossils from the earliest stages of the Cambrian explosion. The mechanisms contributing to its unique preservation, known as the Burgess Shale-type preservation, are well understood. However, little is known about the preservation differences between various animal groups within this biota. This study compares tissue-occurrence data of 11 major animal groups in the Chengjiang biota using a probabilistic methodology. The fossil-based data from this study is compared to previous decay experiments. This shows that all groups are not equally preserved with some higher taxa more likely to preserve soft tissues than others. These differences in fossil preservation between taxa can be explained by the interaction of biological and environmental characteristics. A bias also results from differential taxonomic recognition, as some taxa are easily recognized from even poorly preserved fragments while other specimens are difficult to assign to higher taxa even with exquisite preservation.
Abstract.
Author URL.
Saleh F, Qi C, Buatois LA, Mángano MG, Paz M, Vaucher R, Zheng Q, Hou X-G, Gabbott SE, Ma X, et al (2022). The Chengjiang Biota inhabited a deltaic environment.
Nature Communications,
13(1).
Abstract:
The Chengjiang Biota inhabited a deltaic environment
AbstractThe Chengjiang Biota is the earliest Phanerozoic soft-bodied fossil assemblage offering the most complete snapshot of Earth’s initial diversification, the Cambrian Explosion. Although palaeobiologic aspects of this biota are well understood, the precise sedimentary environment inhabited by this biota remains debated. Herein, we examine a non-weathered core from the Yu’anshan Formation including the interval preserving the Chengjiang Biota. Our data indicate that the succession was deposited as part of a delta influenced by storm floods (i.e. produced by upstream river floods resulting from ocean storms). Most Chengjiang animals lived in an oxygen and nutrient-rich delta front environment in which unstable salinity and high sedimentation rates were the main stressors. This unexpected finding allows for sophisticated ecological comparisons with other Burgess Shale-type deposits and emphasizes that the long-held view of Burgess Shale-type faunas as snapshots of stable distal shelf and slope communities needs to be revised based on recent sedimentologic advances.
Abstract.
Howard RJ, Giacomelli M, Lozano-Fernandez J, Edgecombe GD, Fleming JF, Kristensen RM, Ma X, Olesen J, Sørensen MV, Thomsen PF, et al (2022). The Ediacaran origin of Ecdysozoa: integrating fossil and phylogenomic data.
Journal of the Geological Society,
179(4).
Abstract:
The Ediacaran origin of Ecdysozoa: integrating fossil and phylogenomic data
. Ecdysozoans (Phyla Arthropoda, Kinorhyncha, Loricifera, Nematoda, Nematomorpha, Onychophora, Priapulida, Tardigrada) are invertebrates bearing a tough, periodically moulted cuticle that predisposes them to exceptional preservation. Ecdysozoans dominate the oldest exceptionally preserved bilaterian animal biotas in the early to mid-Cambrian (
. c.
. 520–508â€
Ma), with possible trace fossils in the latest Ediacaran (<556â€
Ma). The fossil record of Ecdysozoa is among the best understood of major animal clades and is believed to document their origins and evolutionary history well. Strikingly, however, molecular clock analyses have implied a considerably deeper Precambrian origin for Ecdysozoa, much older than their earliest fossils. Here, using an improved set of fossil calibrations, we performed Bayesian analyses to estimate an evolutionary time-tree for Ecdysozoa, sampling all eight phyla for the first time. Our results recover Scalidophora as the sister group to Nematoida + Panarthropoda (= Cryptovermes nov.) and suggest that the Ediacaran divergence of Ecdysozoa occurred at least 23â€
myr before the first potential ecdysozoan trace fossils. This finding is impervious to the use of all plausible phylogenies, fossil prior distributions, evolutionary rate models and matrix partitioning strategies. Arthropods exhibit more precision and less incongruence between fossil- and clock-based estimates of clade ages than other ecdysozoan phyla.
.
.
. Supplementary material:
. Full methodologies used and an appendix of fossil calibration points are available at
. https://doi.org/10.6084/m9.figshare.c.5811381
.
.
. Thematic collection:
. This article is part of the Advances in the Cambrian Explosion collection available at:
. https://www.lyellcollection.org/cc/advances-cambrian-explosion
.
Abstract.
Shi X, Howard RJ, Edgecombe GD, Hou X, Ma X (2021). <i>Tabelliscolex</i>(Cricocosmiidae: Palaeoscolecidomorpha) from the early Cambrian Chengjiang Biota and the evolution of seriation in Ecdysozoa. Journal of the Geological Society, 179(2).
Saleh F, Bath-Enright OG, Daley AC, Lefebvre B, Pittet B, Vite A, Ma X, Mángano MG, Buatois LA, Antcliffe JB, et al (2021). A novel tool to untangle the ecology and fossil preservation knot in exceptionally preserved biotas.
Earth and Planetary Science Letters,
569Abstract:
A novel tool to untangle the ecology and fossil preservation knot in exceptionally preserved biotas
Understanding the functioning of extinct ecosystems is a complicated knot of ecological, evolutionary, and preservational strands that must be untangled. For instance, anatomical and behavioral differences can profoundly alter fossilization pathways. This is particularly true in exceptionally preserved soft-bodied biotas that record the earliest phases of animal evolution during the Cambrian Explosion and the Ordovician Radiation. Herein, a novel method of data partitioning based on probabilistic modelling is developed to examine these processes for the Walcott Quarry, Burgess Shale, Canada (510Ma), and the Fezouata Shale, Morocco (c. 475Ma). The modelling shows that the mechanism for soft-tissue preservation in the Walcott Quarry is ecologically selective, favoring the endobenthos. This is not found in the Fezouata Shale. Taken in concert with bioturbation data, a new model of comparative preservation is developed based on sedimentary flow dynamics. This suggests that during the Cambrian Explosion and Ordovician Radiation the most exceptional fossils sites must still be calibrated against each other to understand the unfolding evolutionary events and the ecological structuring of ancient animal communities.
Abstract.
Howard RJ, Hou X, Edgecombe GD, Salge T, Shi X, Ma X (2020). A Tube-Dwelling Early Cambrian Lobopodian.
Curr Biol,
30(8), 1529-1536.e2.
Abstract:
A Tube-Dwelling Early Cambrian Lobopodian.
Facivermis yunnanicus [1, 2] is an enigmatic worm-like animal from the early Cambrian Chengjiang Biota of Yunnan Province, China. It is a small (
Abstract.
Author URL.
Howard RJ, Edgecombe GD, Shi X, Hou X, Ma X (2020). Ancestral morphology of Ecdysozoa constrained by an early Cambrian stem group ecdysozoan.
BMC Evolutionary Biology,
20(1).
Abstract:
Ancestral morphology of Ecdysozoa constrained by an early Cambrian stem group ecdysozoan
Abstract
. Background
. Ecdysozoa are the moulting protostomes, including arthropods, tardigrades, and nematodes. Both the molecular and fossil records indicate that Ecdysozoa is an ancient group originating in the terminal Proterozoic, and exceptional fossil biotas show their dominance and diversity at the beginning of the Phanerozoic. However, the nature of the ecdysozoan common ancestor has been difficult to ascertain due to the extreme morphological diversity of extant Ecdysozoa, and the lack of early diverging taxa in ancient fossil biotas.
.
. Results
. Here we re-describe Acosmia maotiania from the early Cambrian Chengjiang Biota of Yunnan Province, China and assign it to stem group Ecdysozoa. Acosmia features a two-part body, with an anterior proboscis bearing a terminal mouth and muscular pharynx, and a posterior annulated trunk with a through gut. Morphological phylogenetic analyses of the protostomes using parsimony, maximum likelihood and Bayesian inference, with coding informed by published experimental decay studies, each placed Acosmia as sister taxon to Cycloneuralia + Panarthropoda—i.e. stem group Ecdysozoa. Ancestral state probabilities were calculated for key ecdysozoan nodes, in order to test characters inferred from fossils to be ancestral for Ecdysozoa. Results support an ancestor of crown group ecdysozoans sharing an annulated vermiform body with a terminal mouth like Acosmia, but also possessing the pharyngeal armature and circumoral structures characteristic of Cambrian cycloneuralians and lobopodians.
.
. Conclusions
. Acosmia is the first taxon placed in the ecdysozoan stem group and provides a constraint to test hypotheses on the early evolution of Ecdysozoa. Our study suggests acquisition of pharyngeal armature, and therefore a change in feeding strategy (e.g. predation), may have characterised the origin and radiation of crown group ecdysozoans from Acosmia-like ancestors.
.
Abstract.
Zhai D, Williams M, Siveter DJ, Harvey THP, Sansom RS, Gabbott SE, Siveter DJ, Ma X, Zhou R, Liu Y, et al (2019). Variation in appendages in early Cambrian bradoriids reveals a wide range of body plans in stem-euarthropods.
Commun Biol,
2(1).
Abstract:
Variation in appendages in early Cambrian bradoriids reveals a wide range of body plans in stem-euarthropods.
Traditionally, the origin and evolution of modern arthropod body plans has been revealed through increasing levels of appendage specialisation exhibited by Cambrian euarthropods. Here we show significant variation in limb morphologies and patterns of limb-tagmosis among three early Cambrian arthropod species conventionally assigned to the Bradoriida. These arthropods are recovered as a monophyletic stem-euarthropod group (and sister taxon to crown-group euarthropods, i.e. Chelicerata, Mandibulata and their extinct relatives), thus implying a radiation of stem-euarthropods where trends towards increasing appendage specialisation were explored convergently with other euarthropod groups. The alternative solution, where bradoriids are polyphyletic, representing several independent origins of a small, bivalved body plan in lineages from diverse regions of the euarthropod and mandibulate stems, is only marginally less parsimonious. The new data reveal a previously unknown disparity of body plans in stem-euarthropods and both solutions support remarkable evolutionary convergence, either of fundamental body plans or appendage specialization patterns.
Abstract.
Author URL.
Qi C, Li C, Gabbott SE, Ma X, Xie L, Deng W, Jin C, Hou XG (2018). Influence of redox conditions on animal distribution and soft-bodied fossil preservation of the Lower Cambrian Chengjiang Biota.
Palaeogeography, Palaeoclimatology, Palaeoecology,
507, 180-187.
Abstract:
Influence of redox conditions on animal distribution and soft-bodied fossil preservation of the Lower Cambrian Chengjiang Biota
The exceptionally preserved Chengjiang Biota (Yunnan, China) is significant for understanding the rapid development of complex animal-rich ecosystems during the evolutionary radiation of the Cambrian. However, the ecological signal provided by the fossils captured in this deposit may not reflect accurately the in-life community, with transport and decay of carcasses being the principal processes responsible for potential modification. The principal fossil-bearing interval (Maotianshan Shale Member, Yu'anshan Formation) is comprised of claystones of two distinct depositional origins: the “background” beds represent slow hemipelagic deposition into deep waters, while the “event” beds represent distal turbidites or storm-generated beds. Each bed type has a distinct fossil assemblage and preservation mode underscoring the importance of interpreting the palaeoenvironment of each bed type. Here, we interpret palaeo-redox conditions for both the background beds and the event beds by conducting a systematic geochemical study using iron speciation, δ34Spy, δ13Ccarb δ13CTOC and molybdenum abundance. These data are from the most complete core recovered from the Chengjiang fossiliferous units and allow us to distinguish redox conditions where the animals lived, and where they were buried and exceptionally preserved. Our results demonstrate that background beds were dominated by dysoxic conditions; here, a diverse sponge community tolerant of low-oxygen conditions lived. In contrast, the shallower shelf and offshore-transitional environments, where event beds were sourced, were almost persistently oxic, and it was here where the diverse Chengjiang Biota flourished. Thus, the Chengjiang sediments record two distinct palaeocommunities within the background and the event beds. The contrasting redox conditions in close spatial proximity likely facilitated the soft-bodied fossil preservation. Our findings provide a valuable case study in the necessity to understand ecological composition and exceptional preservation informed by environmental context.
Abstract.
Cong P, Ma X, Williams M, Siveter DJ, Siveter DJ, Gabbott SE, Zhai D, Goral T, Edgecombe GD, Hou X, et al (2017). Host-specific infestation in early Cambrian worms. Nature Ecology & Evolution, 1(10), 1465-1469.
Hou X, Williams M, Gabbott S, Siveter DJ, Siveter DJ, Cong P, Ma X, Sansom R (2016). A new species of the artiopodan arthropod <i>Acanthomeridion</i> from the lower Cambrian Chengjiang Lagerstätte, China, and the phylogenetic significance of the genus. Journal of Systematic Palaeontology, 15(9), 733-740.
Strausfeld NJ, Ma X, Edgecombe GD, Fortey RA, Land MF, Liu Y, Cong P, Hou X (2016). Arthropod eyes: the early Cambrian fossil record and divergent evolution of visual systems. Arthropod Structure & Development, 45(2), 152-172.
Strausfeld NJ, Ma X, Edgecombe GD (2016). Fossils and the Evolution of the Arthropod Brain. Current Biology, 26(20), R989-R1000.
Williams M, Siveter DJ, Siveter DJ, Gabbott SE, Ma X, Purnell MA, Cong P (2016). The spectacular fossils of the ‘water margin’: the Cambrian biota of Chengjiang, Yunnan, China. Geology Today, 32(6), 233-237.
Ma X, Aldridge RJ, Siveter DJ, Siveter DJ, Hou X, Edgecombe GD (2015). A New Exceptionally Preserved Cambrian Priapulid from the Chengjiang Lagerstätte.
Journal of Paleontology,
88(2), 371-384.
Abstract:
A New Exceptionally Preserved Cambrian Priapulid from the Chengjiang Lagerstätte
A fossil priapulid, Eximipriapulus globocaudatus new genus new species, is described from the Cambrian Chengjiang Lagerstätte of Yunnan, China. The exceptional preservation of the animal reveals morphological details that allow direct comparison with extant priapulids. The body is divisible into a partially eversible pharynx, a smooth collar, a scalid-bearing introvert, a neck with triangular scalids, an unsegmented trunk with annulations, and a distinctly expanded terminal region. Several specialized regions of the alimentary canal are recognized: a pharynx (lined by cuticle and bearing teeth), esophagus, midgut, hindgut, and a terminal anus. The sample includes a putative juvenile. The animal is inferred to have been an active burrower using a double-anchor strategy, practicing both deposit feeding and carnivory. Inclusion of Eximipriapulus in the most recent character matrix for cladistic analysis of fossil and Recent priapulids resolves the new genus within the priapulid crown group.
Abstract.
Ma X (2015). Hallucigenia's head. Nature, 523(7558), 38-39.
Ma X, Edgecombe GD, Hou X, Goral T, Strausfeld NJ (2015). Preservational Pathways of Corresponding Brains of a Cambrian Euarthropod. Current Biology, 25(22), 2969-2975.
Edgecombe GD, Ma X, Strausfeld NJ (2015). Unlocking the early fossil record of the arthropod central nervous system.
Philosophical Transactions of the Royal Society B: Biological Sciences,
370(1684), 20150038-20150038.
Abstract:
Unlocking the early fossil record of the arthropod central nervous system
. Extant panarthropods (euarthropods, onychophorans and tardigrades) are hallmarked by stunning morphological and taxonomic diversity, but their central nervous systems (CNS) are relatively conserved. The timing of divergences of the ground pattern CNS organization of the major panarthropod clades has been poorly constrained because of a scarcity of data from their early fossil record. Although the CNS has been documented in three-dimensional detail in insects from Cenozoic ambers, it is widely assumed that these tissues are too prone to decay to withstand other styles of fossilization or geologically older preservation. However, Cambrian Burgess Shale-type compressions have emerged as sources of fossilized brains and nerve cords. CNS in these Cambrian fossils are preserved as carbon films or as iron oxides/hydroxides after pyrite in association with carbon. Experiments with carcasses compacted in fine-grained sediment depict preservation of neural tissue for a more prolonged temporal window than anticipated by decay experiments in other media. CNS and compound eye characters in exceptionally preserved Cambrian fossils predict divergences of the mandibulate and chelicerate ground patterns by Cambrian Stage 3 (
. ca
. 518 Ma), a dating that is compatible with molecular estimates for these splits.
.
Abstract.
Ma X, Cong P, Hou X, Edgecombe GD, Strausfeld NJ (2014). An exceptionally preserved arthropod cardiovascular system from the early Cambrian. Nature Communications, 5(1).
Cong P, Ma X, Hou X, Edgecombe GD, Strausfeld NJ (2014). Brain structure resolves the segmental affinity of anomalocaridid appendages. Nature, 513(7519), 538-542.
Cong P, Ma X, Hou X, Edgecombe GD, Strausfeld NJ (2014). Cong et al. reply. Nature, 516(7530), E3-E4.
GarcÃa-bellido DC, Edgecombe GD, Paterson JR, Ma X (2013). A ‘Collins’ monster’-type lobopodian from the Emu Bay Shale Konservat-Lagerstätte (Cambrian), South Australia. Alcheringa: an Australasian Journal of Palaeontology, 37(4), 474-478.
Tanaka G, Hou X, Ma X, Edgecombe GD, Strausfeld NJ (2013). Chelicerate neural ground pattern in a Cambrian great appendage arthropod. Nature, 502(7471), 364-367.
Ma X, Edgecombe GD, Legg DA, Hou X (2013). The morphology and phylogenetic position of the Cambrian lobopodian <i>Diania cactiformis</i>. Journal of Systematic Palaeontology, 12(4), 445-457.
Ma X, Hou X, Edgecombe GD, Strausfeld NJ (2012). Complex brain and optic lobes in an early Cambrian arthropod. Nature, 490(7419), 258-261.
Ma X, Hou X, Aldridge RJ, Siveter DJ, Siveter DJ, Gabbott SE, Purnell MA, Parker AR, Edgecombe GD (2012). Morphology of Cambrian lobopodian eyes from the Chengjiang Lagerstätte and their evolutionary significance. Arthropod Structure & Development, 41(5), 495-504.
Hou X-G, Aldridge RJ, Siveter DJ, Siveter DJ, Williams M, Zalasiewicz J, Ma X-Y (2011). An Early Cambrian Hemichordate Zooid. Current Biology, 21(7), 612-616.
Legg DA, Ma X, Wolfe JM, Ortega-Hernández J, Edgecombe GD, Sutton MD (2011). Lobopodian phylogeny reanalysed. Nature, 476(7359), E1-E1.
Ma X, Hou X, Baines D (2010). Phylogeny and evolutionary significance of vermiform animals from the Early Cambrian Chengjiang Lagerstätte. Science China Earth Sciences, 53(12), 1774-1783.
Ma X, Hou X, Bergström J (2009). Morphology of Luolishania longicruris (Lower Cambrian, Chengjiang Lagerstätte, SW China) and the phylogenetic relationships within lobopodians. Arthropod Structure & Development, 38(4), 271-291.
Xian-Guang H, Bergström J, Xiao-Ya M, Jie Z (2006). The Lower Cambrian<i>Phlogites</i>Luo & Hu re-considered. GFF, 128(1), 47-51.
Hou X, Stanley Jr. GD, Zhao J, Ma X (2005). Cambrian anemones with preserved soft tissue from the Chengjiang biota, China. Lethaia, 38(3), 193-203.
Hou X, Ma X, Zhao J, Bergström J (2004). The lobopodian. <i>Paucipodia inermis</i>. from the Lower Cambrian Chengjiang fauna, Yunnan, China. Lethaia, 37(3), 235-244.
Publications by year
In Press
Chen H, Parry L, Vinther J, Zhai D, Hou X, Ma X (In Press). A Cambrian crown annelid reconciles phylogenomics and the fossil record. Nature
2022
Saleh F, Guenser P, Gibert C, Balseiro D, Serra F, Waisfeld BG, Antcliffe JB, Daley AC, Mángano MG, Buatois LA, et al (2022). Contrasting Early Ordovician assembly patterns highlight the complex initial stages of the Ordovician Radiation.
Sci Rep,
12(1).
Abstract:
Contrasting Early Ordovician assembly patterns highlight the complex initial stages of the Ordovician Radiation.
The Early Ordovician is a key interval for our understanding of the evolution of life on Earth as it lays at the transition between the Cambrian Explosion and the Ordovician Radiation and because the fossil record of the late Cambrian is scarce. In this study, assembly processes of Early Ordovician trilobite and echinoderm communities from the Central Anti-Atlas (Morocco), the Montagne Noire (France), and the Cordillera Oriental (Argentina) are explored. The results show that dispersal increased diachronically in trilobite communities during the Early Ordovician. Dispersal did not increase for echinoderms. Dispersal was most probably proximally triggered by the planktic revolution, the fall in seawater temperatures, changes in oceanic circulation, with an overall control by tectonic frameworks and phylogenetic constraints. The diachronous increase in dispersal within trilobite communities in the Early Ordovician highlights the complexity of ecosystem structuring during the early stages of the Ordovician Radiation. As Early Ordovician regional dispersal was followed by well-documented continental dispersal in the Middle/Late Ordovician, it is possible to consider that alongside a global increase in taxonomic richness, the Ordovician Radiation is also characterized by a gradual increase in dispersal.
Abstract.
Author URL.
Zhang G, Parry LA, Vinther J, Ma X (2022). Exceptional soft tissue preservation reveals a cnidarian affinity for a Cambrian phosphatic tubicolous enigma.
Proceedings of the Royal Society B: Biological Sciences,
289(1986).
Abstract:
Exceptional soft tissue preservation reveals a cnidarian affinity for a Cambrian phosphatic tubicolous enigma
. Exoskeletal dwelling tubes are widespread among extant animals and early fossil assemblages. Exceptional fossils from the Cambrian reveal independent origins of tube dwelling by several clades including cnidarians, lophophorates, annelids, scalidophorans, panarthropods and ambulacrarians. However, most fossil tubes lack preservation of soft parts, making it difficult to understand their affinities and evolutionary significance.
. Gangtoucunia aspera
. (Wulongqing Formation, Cambrian Stage 4) was an annulated, gradually expanding phosphatic tube, with occasional attachments of multiple, smaller juveniles and has previously been interpreted as the dwelling tube of a ‘worm’ (e.g. a scalidophoran), lophophorate or problematicum. Here, we report the first soft tissues from
. Gangtoucunia
. that reveal a smooth body with circumoral tentacles and a blind, spacious gut that is partitioned by septa. This is consistent with cnidarian polyps and phylogenetic analysis resolves
. Gangtoucunia
. as a total group medusozoan. The tube of
. Gangtoucunia
. is phenotypically similar to problematic annulated tubular fossils (e.g.
. Sphenothallus
.
. Byronia
. hyolithelminths), which have been compared to both cnidarians and annelids, and are among the oldest assemblages of skeletal fossils. The cnidarian characters of
. G. aspera
. suggest that these early tubular taxa are best interpreted as cnidarians rather than sessile bilaterians in the absence of contrary soft tissue evidence.
.
Abstract.
Ma X, Wang G, Wang M (2022). Impact of Chinese palaeontology on evolutionary research. Philosophical Transactions of the Royal Society B: Biological Sciences, 377(1847).
Saleh F, Vaucher R, VIDAL M, HARIRI KE, Laibl L, Daley A, Gutiérrez-Marco JC, Candela Y, Harper D, Ortega-Hernández J, et al (2022). New fossil assemblages from the Early Ordovician Fezouata Biota.
Saleh F, Vaucher R, Vidal M, Hariri KE, Laibl L, Daley AC, Gutiérrez-Marco JC, Candela Y, Harper DAT, Ortega-Hernández J, et al (2022). New fossil assemblages from the Early Ordovician Fezouata Biota.
Sci Rep,
12(1).
Abstract:
New fossil assemblages from the Early Ordovician Fezouata Biota.
The Fezouata Biota (Morocco) is a unique Early Ordovician fossil assemblage. The discovery of this biota revolutionized our understanding of Earth's early animal diversifications-the Cambrian Explosion and the Ordovician Radiation-by suggesting an evolutionary continuum between both events. Herein, we describe Taichoute, a new fossil locality from the Fezouata Shale. This locality extends the temporal distribution of fossil preservation from this formation into the upper Floian, while also expanding the range of depositional environments to more distal parts of the shelf. In Taichoute, most animals were transported by density flows, unlike the in-situ preservation of animals recovered in previously investigated Fezouata sites. Taichoute is dominated by three-dimensionally preserved, and heavily sclerotized fragments of large euarthropods-possibly representing nektobenthic/nektic bivalved taxa and/or hurdiid radiodonts. Resolving whether this dominance reflects a legitimate aspect of the original ecosystem or a preservational bias requires an in-depth assessment of the environmental conditions at this site. Nevertheless, Taichoute provides novel preservational and palaeontological insights during a key evolutionary transition in the history of life on Earth.
Abstract.
Author URL.
Saleh F, Ma X, Guenser P, Mángano MG, Buatois LA, Antcliffe JB (2022). Probability-based preservational variations within the early Cambrian Chengjiang biota (China).
PeerJ,
10Abstract:
Probability-based preservational variations within the early Cambrian Chengjiang biota (China).
The Chengjiang biota (Yunnan Province, China) is a treasure trove of soft-bodied animal fossils from the earliest stages of the Cambrian explosion. The mechanisms contributing to its unique preservation, known as the Burgess Shale-type preservation, are well understood. However, little is known about the preservation differences between various animal groups within this biota. This study compares tissue-occurrence data of 11 major animal groups in the Chengjiang biota using a probabilistic methodology. The fossil-based data from this study is compared to previous decay experiments. This shows that all groups are not equally preserved with some higher taxa more likely to preserve soft tissues than others. These differences in fossil preservation between taxa can be explained by the interaction of biological and environmental characteristics. A bias also results from differential taxonomic recognition, as some taxa are easily recognized from even poorly preserved fragments while other specimens are difficult to assign to higher taxa even with exquisite preservation.
Abstract.
Author URL.
Saleh F, Qi C, Buatois LA, Mángano MG, Paz M, Vaucher R, Zheng Q, Hou X-G, Gabbott SE, Ma X, et al (2022). The Chengjiang Biota inhabited a deltaic environment.
Nature Communications,
13(1).
Abstract:
The Chengjiang Biota inhabited a deltaic environment
AbstractThe Chengjiang Biota is the earliest Phanerozoic soft-bodied fossil assemblage offering the most complete snapshot of Earth’s initial diversification, the Cambrian Explosion. Although palaeobiologic aspects of this biota are well understood, the precise sedimentary environment inhabited by this biota remains debated. Herein, we examine a non-weathered core from the Yu’anshan Formation including the interval preserving the Chengjiang Biota. Our data indicate that the succession was deposited as part of a delta influenced by storm floods (i.e. produced by upstream river floods resulting from ocean storms). Most Chengjiang animals lived in an oxygen and nutrient-rich delta front environment in which unstable salinity and high sedimentation rates were the main stressors. This unexpected finding allows for sophisticated ecological comparisons with other Burgess Shale-type deposits and emphasizes that the long-held view of Burgess Shale-type faunas as snapshots of stable distal shelf and slope communities needs to be revised based on recent sedimentologic advances.
Abstract.
Howard RJ, Giacomelli M, Lozano-Fernandez J, Edgecombe GD, Fleming JF, Kristensen RM, Ma X, Olesen J, Sørensen MV, Thomsen PF, et al (2022). The Ediacaran origin of Ecdysozoa: integrating fossil and phylogenomic data.
Journal of the Geological Society,
179(4).
Abstract:
The Ediacaran origin of Ecdysozoa: integrating fossil and phylogenomic data
. Ecdysozoans (Phyla Arthropoda, Kinorhyncha, Loricifera, Nematoda, Nematomorpha, Onychophora, Priapulida, Tardigrada) are invertebrates bearing a tough, periodically moulted cuticle that predisposes them to exceptional preservation. Ecdysozoans dominate the oldest exceptionally preserved bilaterian animal biotas in the early to mid-Cambrian (
. c.
. 520–508â€
Ma), with possible trace fossils in the latest Ediacaran (<556â€
Ma). The fossil record of Ecdysozoa is among the best understood of major animal clades and is believed to document their origins and evolutionary history well. Strikingly, however, molecular clock analyses have implied a considerably deeper Precambrian origin for Ecdysozoa, much older than their earliest fossils. Here, using an improved set of fossil calibrations, we performed Bayesian analyses to estimate an evolutionary time-tree for Ecdysozoa, sampling all eight phyla for the first time. Our results recover Scalidophora as the sister group to Nematoida + Panarthropoda (= Cryptovermes nov.) and suggest that the Ediacaran divergence of Ecdysozoa occurred at least 23â€
myr before the first potential ecdysozoan trace fossils. This finding is impervious to the use of all plausible phylogenies, fossil prior distributions, evolutionary rate models and matrix partitioning strategies. Arthropods exhibit more precision and less incongruence between fossil- and clock-based estimates of clade ages than other ecdysozoan phyla.
.
.
. Supplementary material:
. Full methodologies used and an appendix of fossil calibration points are available at
. https://doi.org/10.6084/m9.figshare.c.5811381
.
.
. Thematic collection:
. This article is part of the Advances in the Cambrian Explosion collection available at:
. https://www.lyellcollection.org/cc/advances-cambrian-explosion
.
Abstract.
2021
Shi X, Howard RJ, Edgecombe GD, Hou X, Ma X (2021). <i>Tabelliscolex</i>(Cricocosmiidae: Palaeoscolecidomorpha) from the early Cambrian Chengjiang Biota and the evolution of seriation in Ecdysozoa. Journal of the Geological Society, 179(2).
Saleh F, Bath-Enright OG, Daley AC, Lefebvre B, Pittet B, Vite A, Ma X, Mángano MG, Buatois LA, Antcliffe JB, et al (2021). A novel tool to untangle the ecology and fossil preservation knot in exceptionally preserved biotas.
Earth and Planetary Science Letters,
569Abstract:
A novel tool to untangle the ecology and fossil preservation knot in exceptionally preserved biotas
Understanding the functioning of extinct ecosystems is a complicated knot of ecological, evolutionary, and preservational strands that must be untangled. For instance, anatomical and behavioral differences can profoundly alter fossilization pathways. This is particularly true in exceptionally preserved soft-bodied biotas that record the earliest phases of animal evolution during the Cambrian Explosion and the Ordovician Radiation. Herein, a novel method of data partitioning based on probabilistic modelling is developed to examine these processes for the Walcott Quarry, Burgess Shale, Canada (510Ma), and the Fezouata Shale, Morocco (c. 475Ma). The modelling shows that the mechanism for soft-tissue preservation in the Walcott Quarry is ecologically selective, favoring the endobenthos. This is not found in the Fezouata Shale. Taken in concert with bioturbation data, a new model of comparative preservation is developed based on sedimentary flow dynamics. This suggests that during the Cambrian Explosion and Ordovician Radiation the most exceptional fossils sites must still be calibrated against each other to understand the unfolding evolutionary events and the ecological structuring of ancient animal communities.
Abstract.
2020
Howard RJ, Hou X, Edgecombe GD, Salge T, Shi X, Ma X (2020). A Tube-Dwelling Early Cambrian Lobopodian.
Curr Biol,
30(8), 1529-1536.e2.
Abstract:
A Tube-Dwelling Early Cambrian Lobopodian.
Facivermis yunnanicus [1, 2] is an enigmatic worm-like animal from the early Cambrian Chengjiang Biota of Yunnan Province, China. It is a small (
Abstract.
Author URL.
Howard RJ, Edgecombe GD, Shi X, Hou X, Ma X (2020). Ancestral morphology of Ecdysozoa constrained by an early Cambrian stem group ecdysozoan.
BMC Evolutionary Biology,
20(1).
Abstract:
Ancestral morphology of Ecdysozoa constrained by an early Cambrian stem group ecdysozoan
Abstract
. Background
. Ecdysozoa are the moulting protostomes, including arthropods, tardigrades, and nematodes. Both the molecular and fossil records indicate that Ecdysozoa is an ancient group originating in the terminal Proterozoic, and exceptional fossil biotas show their dominance and diversity at the beginning of the Phanerozoic. However, the nature of the ecdysozoan common ancestor has been difficult to ascertain due to the extreme morphological diversity of extant Ecdysozoa, and the lack of early diverging taxa in ancient fossil biotas.
.
. Results
. Here we re-describe Acosmia maotiania from the early Cambrian Chengjiang Biota of Yunnan Province, China and assign it to stem group Ecdysozoa. Acosmia features a two-part body, with an anterior proboscis bearing a terminal mouth and muscular pharynx, and a posterior annulated trunk with a through gut. Morphological phylogenetic analyses of the protostomes using parsimony, maximum likelihood and Bayesian inference, with coding informed by published experimental decay studies, each placed Acosmia as sister taxon to Cycloneuralia + Panarthropoda—i.e. stem group Ecdysozoa. Ancestral state probabilities were calculated for key ecdysozoan nodes, in order to test characters inferred from fossils to be ancestral for Ecdysozoa. Results support an ancestor of crown group ecdysozoans sharing an annulated vermiform body with a terminal mouth like Acosmia, but also possessing the pharyngeal armature and circumoral structures characteristic of Cambrian cycloneuralians and lobopodians.
.
. Conclusions
. Acosmia is the first taxon placed in the ecdysozoan stem group and provides a constraint to test hypotheses on the early evolution of Ecdysozoa. Our study suggests acquisition of pharyngeal armature, and therefore a change in feeding strategy (e.g. predation), may have characterised the origin and radiation of crown group ecdysozoans from Acosmia-like ancestors.
.
Abstract.
2019
Zhai D, Williams M, Siveter DJ, Harvey THP, Sansom RS, Gabbott SE, Siveter DJ, Ma X, Zhou R, Liu Y, et al (2019). Variation in appendages in early Cambrian bradoriids reveals a wide range of body plans in stem-euarthropods.
Commun Biol,
2(1).
Abstract:
Variation in appendages in early Cambrian bradoriids reveals a wide range of body plans in stem-euarthropods.
Traditionally, the origin and evolution of modern arthropod body plans has been revealed through increasing levels of appendage specialisation exhibited by Cambrian euarthropods. Here we show significant variation in limb morphologies and patterns of limb-tagmosis among three early Cambrian arthropod species conventionally assigned to the Bradoriida. These arthropods are recovered as a monophyletic stem-euarthropod group (and sister taxon to crown-group euarthropods, i.e. Chelicerata, Mandibulata and their extinct relatives), thus implying a radiation of stem-euarthropods where trends towards increasing appendage specialisation were explored convergently with other euarthropod groups. The alternative solution, where bradoriids are polyphyletic, representing several independent origins of a small, bivalved body plan in lineages from diverse regions of the euarthropod and mandibulate stems, is only marginally less parsimonious. The new data reveal a previously unknown disparity of body plans in stem-euarthropods and both solutions support remarkable evolutionary convergence, either of fundamental body plans or appendage specialization patterns.
Abstract.
Author URL.
2018
Qi C, Li C, Gabbott SE, Ma X, Xie L, Deng W, Jin C, Hou XG (2018). Influence of redox conditions on animal distribution and soft-bodied fossil preservation of the Lower Cambrian Chengjiang Biota.
Palaeogeography, Palaeoclimatology, Palaeoecology,
507, 180-187.
Abstract:
Influence of redox conditions on animal distribution and soft-bodied fossil preservation of the Lower Cambrian Chengjiang Biota
The exceptionally preserved Chengjiang Biota (Yunnan, China) is significant for understanding the rapid development of complex animal-rich ecosystems during the evolutionary radiation of the Cambrian. However, the ecological signal provided by the fossils captured in this deposit may not reflect accurately the in-life community, with transport and decay of carcasses being the principal processes responsible for potential modification. The principal fossil-bearing interval (Maotianshan Shale Member, Yu'anshan Formation) is comprised of claystones of two distinct depositional origins: the “background” beds represent slow hemipelagic deposition into deep waters, while the “event” beds represent distal turbidites or storm-generated beds. Each bed type has a distinct fossil assemblage and preservation mode underscoring the importance of interpreting the palaeoenvironment of each bed type. Here, we interpret palaeo-redox conditions for both the background beds and the event beds by conducting a systematic geochemical study using iron speciation, δ34Spy, δ13Ccarb δ13CTOC and molybdenum abundance. These data are from the most complete core recovered from the Chengjiang fossiliferous units and allow us to distinguish redox conditions where the animals lived, and where they were buried and exceptionally preserved. Our results demonstrate that background beds were dominated by dysoxic conditions; here, a diverse sponge community tolerant of low-oxygen conditions lived. In contrast, the shallower shelf and offshore-transitional environments, where event beds were sourced, were almost persistently oxic, and it was here where the diverse Chengjiang Biota flourished. Thus, the Chengjiang sediments record two distinct palaeocommunities within the background and the event beds. The contrasting redox conditions in close spatial proximity likely facilitated the soft-bodied fossil preservation. Our findings provide a valuable case study in the necessity to understand ecological composition and exceptional preservation informed by environmental context.
Abstract.
2017
Cong P, Ma X, Williams M, Siveter DJ, Siveter DJ, Gabbott SE, Zhai D, Goral T, Edgecombe GD, Hou X, et al (2017). Host-specific infestation in early Cambrian worms. Nature Ecology & Evolution, 1(10), 1465-1469.
Xian-Guang H, Aldridge RJ, Pei-Yun C, Siveter DJ, Siveter DJ, Gabbott SE, Xiao-Ya M, Purnell MA, Williams M (2017).
The Cambrian Fossils of Chengjiang, China the Flowering of Early Animal Life., John Wiley & Sons.
Abstract:
The Cambrian Fossils of Chengjiang, China the Flowering of Early Animal Life
Abstract.
2016
Hou X, Williams M, Gabbott S, Siveter DJ, Siveter DJ, Cong P, Ma X, Sansom R (2016). A new species of the artiopodan arthropod <i>Acanthomeridion</i> from the lower Cambrian Chengjiang Lagerstätte, China, and the phylogenetic significance of the genus. Journal of Systematic Palaeontology, 15(9), 733-740.
Strausfeld NJ, Ma X, Edgecombe GD, Fortey RA, Land MF, Liu Y, Cong P, Hou X (2016). Arthropod eyes: the early Cambrian fossil record and divergent evolution of visual systems. Arthropod Structure & Development, 45(2), 152-172.
Strausfeld NJ, Ma X, Edgecombe GD (2016). Fossils and the Evolution of the Arthropod Brain. Current Biology, 26(20), R989-R1000.
Williams M, Siveter DJ, Siveter DJ, Gabbott SE, Ma X, Purnell MA, Cong P (2016). The spectacular fossils of the ‘water margin’: the Cambrian biota of Chengjiang, Yunnan, China. Geology Today, 32(6), 233-237.
2015
Ma X, Aldridge RJ, Siveter DJ, Siveter DJ, Hou X, Edgecombe GD (2015). A New Exceptionally Preserved Cambrian Priapulid from the Chengjiang Lagerstätte.
Journal of Paleontology,
88(2), 371-384.
Abstract:
A New Exceptionally Preserved Cambrian Priapulid from the Chengjiang Lagerstätte
A fossil priapulid, Eximipriapulus globocaudatus new genus new species, is described from the Cambrian Chengjiang Lagerstätte of Yunnan, China. The exceptional preservation of the animal reveals morphological details that allow direct comparison with extant priapulids. The body is divisible into a partially eversible pharynx, a smooth collar, a scalid-bearing introvert, a neck with triangular scalids, an unsegmented trunk with annulations, and a distinctly expanded terminal region. Several specialized regions of the alimentary canal are recognized: a pharynx (lined by cuticle and bearing teeth), esophagus, midgut, hindgut, and a terminal anus. The sample includes a putative juvenile. The animal is inferred to have been an active burrower using a double-anchor strategy, practicing both deposit feeding and carnivory. Inclusion of Eximipriapulus in the most recent character matrix for cladistic analysis of fossil and Recent priapulids resolves the new genus within the priapulid crown group.
Abstract.
Ma X (2015). Hallucigenia's head. Nature, 523(7558), 38-39.
Ma X, Edgecombe GD, Hou X, Goral T, Strausfeld NJ (2015). Preservational Pathways of Corresponding Brains of a Cambrian Euarthropod. Current Biology, 25(22), 2969-2975.
Edgecombe GD, Ma X, Strausfeld NJ (2015). Unlocking the early fossil record of the arthropod central nervous system.
Philosophical Transactions of the Royal Society B: Biological Sciences,
370(1684), 20150038-20150038.
Abstract:
Unlocking the early fossil record of the arthropod central nervous system
. Extant panarthropods (euarthropods, onychophorans and tardigrades) are hallmarked by stunning morphological and taxonomic diversity, but their central nervous systems (CNS) are relatively conserved. The timing of divergences of the ground pattern CNS organization of the major panarthropod clades has been poorly constrained because of a scarcity of data from their early fossil record. Although the CNS has been documented in three-dimensional detail in insects from Cenozoic ambers, it is widely assumed that these tissues are too prone to decay to withstand other styles of fossilization or geologically older preservation. However, Cambrian Burgess Shale-type compressions have emerged as sources of fossilized brains and nerve cords. CNS in these Cambrian fossils are preserved as carbon films or as iron oxides/hydroxides after pyrite in association with carbon. Experiments with carcasses compacted in fine-grained sediment depict preservation of neural tissue for a more prolonged temporal window than anticipated by decay experiments in other media. CNS and compound eye characters in exceptionally preserved Cambrian fossils predict divergences of the mandibulate and chelicerate ground patterns by Cambrian Stage 3 (
. ca
. 518 Ma), a dating that is compatible with molecular estimates for these splits.
.
Abstract.
2014
Ma X, Cong P, Hou X, Edgecombe GD, Strausfeld NJ (2014). An exceptionally preserved arthropod cardiovascular system from the early Cambrian. Nature Communications, 5(1).
Cong P, Ma X, Hou X, Edgecombe GD, Strausfeld NJ (2014). Brain structure resolves the segmental affinity of anomalocaridid appendages. Nature, 513(7519), 538-542.
Cong P, Ma X, Hou X, Edgecombe GD, Strausfeld NJ (2014). Cong et al. reply. Nature, 516(7530), E3-E4.
2013
GarcÃa-bellido DC, Edgecombe GD, Paterson JR, Ma X (2013). A ‘Collins’ monster’-type lobopodian from the Emu Bay Shale Konservat-Lagerstätte (Cambrian), South Australia. Alcheringa: an Australasian Journal of Palaeontology, 37(4), 474-478.
Tanaka G, Hou X, Ma X, Edgecombe GD, Strausfeld NJ (2013). Chelicerate neural ground pattern in a Cambrian great appendage arthropod. Nature, 502(7471), 364-367.
Ma X, Edgecombe GD, Legg DA, Hou X (2013). The morphology and phylogenetic position of the Cambrian lobopodian <i>Diania cactiformis</i>. Journal of Systematic Palaeontology, 12(4), 445-457.
2012
Ma X, Hou X, Edgecombe GD, Strausfeld NJ (2012). Complex brain and optic lobes in an early Cambrian arthropod. Nature, 490(7419), 258-261.
Ma X, Hou X, Aldridge RJ, Siveter DJ, Siveter DJ, Gabbott SE, Purnell MA, Parker AR, Edgecombe GD (2012). Morphology of Cambrian lobopodian eyes from the Chengjiang Lagerstätte and their evolutionary significance. Arthropod Structure & Development, 41(5), 495-504.
2011
Hou X-G, Aldridge RJ, Siveter DJ, Siveter DJ, Williams M, Zalasiewicz J, Ma X-Y (2011). An Early Cambrian Hemichordate Zooid. Current Biology, 21(7), 612-616.
Legg DA, Ma X, Wolfe JM, Ortega-Hernández J, Edgecombe GD, Sutton MD (2011). Lobopodian phylogeny reanalysed. Nature, 476(7359), E1-E1.
2010
Ma X, Hou X, Baines D (2010). Phylogeny and evolutionary significance of vermiform animals from the Early Cambrian Chengjiang Lagerstätte. Science China Earth Sciences, 53(12), 1774-1783.
2009
Ma X, Hou X, Bergström J (2009). Morphology of Luolishania longicruris (Lower Cambrian, Chengjiang Lagerstätte, SW China) and the phylogenetic relationships within lobopodians. Arthropod Structure & Development, 38(4), 271-291.
2006
Xian-Guang H, Bergström J, Xiao-Ya M, Jie Z (2006). The Lower Cambrian<i>Phlogites</i>Luo & Hu re-considered. GFF, 128(1), 47-51.
2005
Hou X, Stanley Jr. GD, Zhao J, Ma X (2005). Cambrian anemones with preserved soft tissue from the Chengjiang biota, China. Lethaia, 38(3), 193-203.
2004
Hou X, Ma X, Zhao J, Bergström J (2004). The lobopodian. <i>Paucipodia inermis</i>. from the Lower Cambrian Chengjiang fauna, Yunnan, China. Lethaia, 37(3), 235-244.