The evolution of hominin ontogenies

Since the beginnings of paleoanthropology, immature fossil hominin specimens have marked important but highly contested cornerstones of research. Long deemed as not representative of a fossil species’ morphology, immature hominins are now in the center of scientific attention, and an increasing interest in evolutionary developmental questions has made developmental paleoanthropology a vibrant field of research. Here we report on recent advances in this field, which result from a combination of new methods to reconstruct fossil ontogenies with insights from evo-devo research on extant species.     

Japanese marine algae: New combinations, new names and new species

Several new species, combinations and names are described or proposed for the following species of algae reported from Japan: Gloiocladia japonica comb. nov. (=Gloioderma japonicum Okamura), Mazzaella hemisphaerica comb. nov. (=Rhodoglos-sum hemisphaericum Mikami), Melanamansia mitsuii comb. nov. (=Amansia mitsuii Segawa), Ptilo-cladia divaricata comb. nov. (=Crouania divaricata Okamura), Analipus gunjii comb. nov. (=Chordaria gunjii Yendo), Elachista okarnurae nom. nov. (=Elachista globosa Takamatsu), Gelidium inagakii nom. nov. (=Gelidium nanum Inagaki), Mastocarpus yendoisp. nov. (=Gigartina mamillosa sensu Yendo), Melobesia masakii nom. nov. (=Metobesia pacifica Masaki) and Porphyra yamadae sp. nov. (=Porphyra crispata sensu Okamura and Ueda).     

The estimation and evolution of hominin body mass

Body mass is a critical variable in many hominin evolutionary studies, with implications for reconstructing relative brain size, diet, locomotion, subsistence strategy, and social organization. We review methods that have been proposed for estimating body mass from true and trace fossils, consider their applicability in different contexts, and the appropriateness of different modern reference samples. Recently developed techniques based on a wider range of modern populations hold promise for providing more accurate estimates in earlier hominins, although uncertainties remain, particularly in non-Homo taxa. When these methods are applied to almost 300 Late Miocene through Late Pleistocene specimens, the resulting body mass estimates fall within a 25–60 kg range for early non-Homo taxa, increase in early Homo to about 50–90 kg, then remain constant until the Terminal Pleistocene, when they decline.     

Correlates and catalysts of hominin evolution in Africa

Hominin evolution in the African Pliocene and Pleistocene was accompanied and mediated by changes in the abiotic and biotic spheres. It has been hypothesized that such environmental changes were catalysts of hominin morphological evolution and speciations. Whereas there is little doubt that ecological changes were relevant to shaping the trajectories of mammalian evolution, testing specific hypotheses with data from the fossil record has yielded ambiguous results regarding environmental disruption as a primary catalyst. Proposed mechanisms for abiotic and biotic causes of evolution are not always consistent with the timing and trends exhibited by the African fossil record of hominins and other mammals. Analyses of fossil and genetic data suggest that much of hominin evolution, and by extension mammalian evolution, was autocatalytic, driven by feedback loops within a species or lineage, irrespective of changes in the external environment.     

Divergent evolution in enolase superfamily: strategies for assigning functions

Nature's strategies for evolving catalytic functions can be deciphered from the information contained in the rapidly expanding protein sequence databases. However, the functions of many proteins in the protein sequence and structure databases are either uncertain (too divergent to assign function based on homology) or unknown (no homologs), thereby limiting the utility of the databases. The mechanistically diverse enolase superfamily is a paradigm for understanding the structural bases for evolution of enzymatic function. We describe strategies for assigning functions to members of the enolase superfamily that should be applicable to other superfamilies.     

Conclusions: implications of the Liang Bua excavations for hominin evolution and biogeography

Excavations at Liang Bua, on the Indonesian island of Flores, have yielded a stratified sequence of stone artifacts and faunal remains spanning the last 95 k.yr., which includes the skeletal remains of two human species, Homo sapiens in the Holocene and Homo floresiensis in the Pleistocene. This paper summarizes and focuses on some of the evidence for Homo floresiensis in context, as presented in this Special Issue edition of the Journal of Human Evolution and elsewhere. Attempts to dismiss the Pleistocene hominins (and the type specimen LB1 in particular) as pathological pygmy humans are not compatible with detailed analyses of the skull, teeth, brain endocast, and postcranium. We initially concluded that H. floresiensis may have evolved by insular dwarfing of a larger-bodied hominin species over 880 k.yr. or more. However, recovery of additional specimens and the numerous primitive morphological traits seen throughout the skeleton suggest instead that it is more likely to be a late representative of a small-bodied lineage that exited Africa before the emergence of Homo erectus sensu lato. Homo floresiensis is clearly not an australopithecine, but does retain many aspects of anatomy (and perhaps behavior) that are probably plesiomorphic for the genus Homo. We also discuss some of the other implications of this tiny, endemic species for early hominin dispersal and evolution (e.g., for the “Out of Africa 1” paradigm and more specifically for colonizing Southeast Asia), and we present options for future research in the region.     

Pandora's growing box: Inferring the evolution and development of hominin brains from endocasts

The brain of modern humans is an evolutionary and developmental outlier: At birth, it has the size of an adult chimpanzee brain and expands by a factor of 2 during the first postnatal year. Large neonatal brain size and rapid initial growth contrast with slow maturation, which extends well into adolescence. When, how, and why this peculiar pattern of brain ontogeny evolved and how it is correlated with structural changes in the brain are key questions of paleoanthropology. Because brains and their ontogenies do not fossilize, indirect evidence from fossil hominin endocasts needs to be combined with evidence from modern humans and our closest living relatives, the great apes. New fossil finds permit a denser sampling of hominin endocranial morphologies along ontogenetic and evolutionary time lines. New brain imaging methods provide the basis for quantifying endocast‐brain relationships and tracking endocranial and brain growth and development noninvasively. Combining this evidence with ever‐more detailed knowledge about actual and fossil “brain genes,” we are now beginning to understand how brain ontogeny and structure were modified during human evolution and what the adaptive significance of these modifications may have been.     

New species, newly used names and new ranges of tree ferns (Filicales: Cyatheaceae) in the Neotropics

Two new species are described for the Neotropics, four species are newly accepted, and four species and one variety are reported. The new species are: Cyathea grayumii A. Rojas and C. panamensis A. Rojas. Cyathea alfonsiana L. D. Gómez, C. holdridgeana Nisman & L. D. Gómez, C. onusta H. Christ and C. squarrosa (Rosenst.) Domin are recognized; Cnemidaria coclena Stolze, Cyathea andina (H. Karst.) Domin, C. caracasana var. meridensis (H. Karst.) R. M. Tryon, C. macrosora (Baker) Domin and C. pseudonanna (L. D. Gómez) Lellinger are reported from Costa Rica and Panama.     

A new species of nightjar from Zaïre

Prigogine's Nightjar Caprimulgus prigoginei is described from a single skin collected in 1955 in Itombwe, eastern Zaïre. The species is unknown in life. Because of its distinct morphology: rather stiff feathers, small tail/wing proportion, broad head, short rictal bristles and its speckled plumage, it is considered to be without close relatives.     

The multiperspectival nature of place names: Ewenki mobility,river naming,and relationships with animals,spirits, and landscapes

The article examines the process of production and change of place names based on data collected in 2017 among the Okhotsk Ewenki, the easternmost Indigenous community in Siberia, Russia. Through ethnographic and semiotic analysis, we show that Ewenki place names are not simply reproduced, but rather generated and transformed through empathic contact and engagement within a semiotic circle of shared knowledge and praxis among humans and other beings encountered, especially in ambulatory travel. We consider place names as complex signs which evolve from landscape, mobility as a spatial practice, and relationships with nonhuman beings. Through ecosemiotics and nonhuman ontology, we examine how the concept of shifting landscapes and interactions with different environmental agents, especially animals, contribute to the production of space and place names and their changes. We also show that the responsible voicing of the land with place names is related to Ewenki understandings of territorial prerogatives, and rights, which are perceived as being shared with other beings.     

Liang Bua Homo floresiensis mandibles and mandibular teeth: a contribution to the comparative morphology of a new hominin species

In 2004, a new hominin species, Homo floresiensis, was described from Late Pleistocene cave deposits at Liang Bua, Flores. H. floresiensis was remarkable for its small body-size, endocranial volume in the chimpanzee range, limb proportions and skeletal robusticity similar to Pliocene Australopithecus, and a skeletal morphology with a distinctive combination of symplesiomorphic, derived, and unique traits. Critics of H. floresiensis as a novel species have argued that the Pleistocene skeletons from Liang Bua either fall within the range of living Australomelanesians, exhibit the attributes of growth disorders found in modern humans, or a combination of both. Here we describe the morphology of the LB1, LB2, and LB6 mandibles and mandibular teeth from Liang Bua. Morphological and metrical comparisons of the mandibles demonstrate that they share a distinctive suite of traits that place them outside both the H. sapiens and H. erectus ranges of variation. While having the derived molar size of later Homo, the symphyseal, corpus, ramus, and premolar morphologies share similarities with both Australopithecus and early Homo. When the mandibles are considered with the existing evidence for cranial and postcranial anatomy, limb proportions, and the functional anatomy of the wrist and shoulder, they are in many respects closer to African early Homo or Australopithecus than to later Homo. Taken together, this evidence suggests that the ancestors of H. floresiensis left Africa before the evolution of H. erectus, as defined by the Dmanisi and East African evidence.     

中国三种稻缘蝽名称订正(半翅目:蛛缘蝽科)

本文梳理了我国常见水稻重要害虫稻缘蝽属3个物种中文名称使用混乱问题,对其常见种中文名称做出如下订正:Leptocorisa acuta(Thunberg,1783)中文名为异稻缘蝽;Leptocorisa chinensis Dallas,1852中文名为中稻缘蝽;Leptocorisa oratoria(Fabricius,1794)中文名为大稻缘蝽,以便于名称的统一和规范,并提供了修订后的中国稻缘蝽5个已记录种的检索表。