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The archaeological sequence at Kasteelberg B, in the Western Cape of South Africa, spans a millennium and covers several distinct occupational phases in the early pastoralist settlement history of the region. Attempts to understand that history through coordinating archaeological, linguistic and genetic evidence have proved problematic. The refined programme of radiocarbon dating presented here sheds further light on the different phases of occupation. More remarkably, it suggests, despite changes in material culture, the persistence of a single population over time, rather than population replacement as has been previously conjectured.

Phylogenetic analysis of a data matrix of 86 skeletal characteristics, and of the first 400 bases of the 5’ end of the large subunit ribosomal RNA gene produce congruent cladograms for 11 extant echinoids. Based on these cladistic analyses the great majority of morphologic and molecular apomorphies can be placed in one of 18 independent geological time intervals. When the cladogram is calibrated using the fossil record of post-Paleozoic echinoids, rates of molecular change in 28S rRNA can be calculated and compared with estimated rates of morphological evolution.

Morphological and molecular apomorphies acquired in each time interval both correlate moderately strongly with time elapsed, but less strongly with one another. As expected, morphological rates vary considerably over time and between sister groups, but so too do molecular rates. When averaged over all echinoids studied, the number of morphological apomorphies accrued yields a slightly higher Spearman Rank correlation coefficient with time elapsed than does the number of molecular apomorphies accrued. This is because there is a three-fold difference in the rate of molecular change amongst the echinoid lineages studied.

We present low-frequency spectral energy distributions of 60 known radio pulsars observed with the Murchison Widefield Array telescope. We searched the GaLactic and Extragalactic All-sky Murchison Widefield Array survey images for 200-MHz continuum radio emission at the position of all pulsars in the Australia Telescope National Facility (ATNF) pulsar catalogue. For the 60 confirmed detections, we have measured flux densities in 20 × 8 MHz bands between 72 and 231 MHz. We compare our results to existing measurements and show that the Murchison Widefield Array flux densities are in good agreement.

Approximately half of the variation in wellbeing measures overlaps with variation in personality traits. Studies of non-human primate pedigrees and human twins suggest that this is due to common genetic influences. We tested whether personality polygenic scores for the NEO Five-Factor Inventory (NEO-FFI) domains and for item response theory (IRT) derived extraversion and neuroticism scores predict variance in wellbeing measures. Polygenic scores were based on published genome-wide association (GWA) results in over 17,000 individuals for the NEO-FFI and in over 63,000 for the IRT extraversion and neuroticism traits. The NEO-FFI polygenic scores were used to predict life satisfaction in 7 cohorts, positive affect in 12 cohorts, and general wellbeing in 1 cohort (maximal N = 46,508). Meta-analysis of these results showed no significant association between NEO-FFI personality polygenic scores and the wellbeing measures. IRT extraversion and neuroticism polygenic scores were used to predict life satisfaction and positive affect in almost 37,000 individuals from UK Biobank. Significant positive associations (effect sizes <0.05%) were observed between the extraversion polygenic score and wellbeing measures, and a negative association was observed between the polygenic neuroticism score and life satisfaction. Furthermore, using GWA data, genetic correlations of -0.49 and -0.55 were estimated between neuroticism with life satisfaction and positive affect, respectively. The moderate genetic correlation between neuroticism and wellbeing is in line with twin research showing that genetic influences on wellbeing are also shared with other independent personality domains.

In their 2013 book Reimagining Business History, Philip Scranton and Patrick Fridenson called on business historians to reassess militarization and the “two-way exchanges” between the military and the private sector. The call is timely. The extensive business-historical scholarship on the relationship between companies and war sensibly focuses on companies that profited from their involvement in the military-industrial complex. 1 The business-historical literature is virtually silent, however, on the role of business in preventing wars from starting in the first place. In other words, business historians have missed a productive opportunity to engage with capitalist peace theory (CPT), an increasingly important theory in the discipline of international relations (IR). Many IR scholars now argue that the mutual economic interdependence characteristic of global capitalism reduces the likelihood of war. Their research suggests that while extensive cross-border economic linkages do not preclude the possibility of war, the creation of a transnational community of economic interests tends, ceteris paribus, to reduce the frequency, duration, and intensity of warfare. 2

The consensus view that the amount of rock available for sampling does not significantly and systematically bias Phanerozoic marine diversity patterns has broken down. How changes in rock availability and sampling intensity affect our estimates of past biodiversity has been investigated with a variety of new approaches. A number of proxies for the amount of rock available for sampling have been used, but most of these proxies do not rely directly on evidence from large-scale geological maps (maps that cover small areas) and accompanying memoirs. Most previous map-based studies focused on single regions or relied on small-scale synoptic maps. We collected data from published geological maps and memoirs from western Europe, Australia, and Chile, which we combined with COSUNA data from the United States to generate the first multiregional data set for investigating whether the global Phanerozoic marine diversity record is a true global record, or is instead biased toward North America and Western Europe as has long been suspected. Both short and long-term trends in variation in the amount of outcrop display limited correlation among the regions studied. A series of diversification models obtained better matches to observed fossil diversity from the European and U.S. records than for the Chilean and Australian records, further supporting suspicions that the global Phanerozoic diversity curve is disproportionately influenced by European and U.S. fossil data. These results indicate that future research into Phanerozoic marine diversity patterns should not continue to apply global eustatic curves as a proxy for rock at outcrop, but should use regional data on rock occurrence.

It has recently been argued that barren intervals of marine sedimentary rock are less common in the Cenozoic than in the Paleozoic, and that this arises as a direct consequence of widespread epeiric seas and the prevalence of dysaerobic conditions at such times. We show, using an independent and more direct measure of rock outcrop through time in western Europe, that barren marine sedimentary rocks do become less frequent toward the present, but that this is not linked to any epeiric-seas effect. The proportion of barren to fossiliferous rock outcrop correlates well with the inferred Phanerozoic marine diversity curve (although more so in the Paleozoic than in the post-Paleozoic), and shows no correlation or only a weak negative correlation with area over which the sediments have been deposited. We therefore concluded that the Phanerozoic trend in fossiliferousness most likely records the degree to which space is occupied in the shallow marine realm.

Paleontological data have for long been paramount in providing a long-term perspective on global biodiversity. But all is not as simple and secure as it once seemed. Apparently rapid diversification events recorded in the fossil record have been challenged by new molecular data (Bromham et al. 1999; Wray 2001; reviewed in Smith and Peterson 2002), certain mass extinctions are not as well founded as was previously supposed (Smith et al. 2001; Peters and Foote 2002b), and even such a deeply cherished belief as the long-term trend of increasing diversity through the Phanerozoic is once again under question (Alroy et al. 2001; Peters and Foote 2002a). Why is the fossil record not currently providing us with reliable, clear-cut data, and what can be done to correct the situation?

Large-scale trends in planktonic foraminiferal diversity have so far been based on utilization of synoptic biostratigraphic range charts. Although this approach ensures the taxonomic consistency and quality of the data being used, it takes no formal account of any sampling biases that might exist in the fossil record. We demonstrate that the occurrence data of planktonic foraminifera, as recorded in the primary literature, are strongly biased by sampling. We do this by demonstrating that raw diversity curves derived from the land-based and deep-sea records are strikingly different, but that they each correlate with the intensity of sampling in their respective environments, and thus are ultimately controlled by the structure of the geological record in each setting. Because sampling of the Mesozoic record is best in our land record whereas sampling of the Cenozoic is best in our deep-sea record, we combine the two to generate the best-supported estimates of species and genus diversity over time from these data. We correct for sampling bias using shareholder quorum subsampling and a modeling approach. The data are then transformed to generate a range-through plot of species richness that is compared with two earlier estimates of the diversity history where comparable species-in-bin data can be recovered. No robust statistical correlation is found among the three estimates. Although differences in amplitude are to be expected, differences in the actual shape of the curve are surprising. We conclude that these differences stem from the nature of the data themselves, namely the taxonomic scheme adopted and the taxonomic coverage used.

The reconstruction of phylogenies using cladistic methods is a powerful and well-established tool for evolutionary biologists and paleobiologists. Indeed, the construction of rigorous phylogenetic hypotheses has become widely accepted as an essential first step in the analysis of historical patterns for both extant and extinct organisms. In the past few years, there has arisen a healthy and constructive debate as to the exact methods that will lead to the most accurate tree (for example whether statistical inference or stratigraphic information has any part to play in phylogenetic reconstruction). Although important, this debate has tended to focus on the problems of tree construction and divert attention away from the applications of tree-based research. The construction of a phylogeny is, after all, only a first step, and phylogenetic trees provide the starting point from which to address a wide range of interesting biological and geological topics.

Molecular data are becoming an indispensable tool for the reconstruction of phylogenies. Fossil molecular data remain scarce, but have the potential to resolve patterns of deep branching and provide empirical tests of tree reconstruction techniques. A total evidence approach, combining and comparing complementary morphological, molecular and stratigraphical data from both recent and fossil taxa, is advocated as the most promising way forward because there are several well-established problems that can afflict the analysis of molecular sequence data sometimes resulting in spurious tree topologies. The integration of evidence allows us to: (1) choose suitable taxa for molecular phylogenetic analysis for the question at hand; (2) discriminate between conflicting hypotheses of taxonomic relationship and phylogeny; (3) evaluate procedures and assumptions underlying methods of building trees; and (4) estimate rates of molecular evolution in the geological past. Paleontology offers a set of independent data for comparison and corroboration of analyses and provides the only direct means of calibrating molecular trees, thus giving insight into rates of molecular evolution in the geological past.

The association between mass extinction in the marine realm and eustatic sea-level change in the Mesozoic is well documented, but perplexing, because it seems implausible that sea-level change could actually cause a major extinction. However, large-scale cycles of sea-level change can and do alter the ratio of shallow to deep marine continental-shelf deposits preserved in the rock record both regionally and globally. This taphonomic megabias alone could be driving patterns of first and last occurrence and standing diversity because diversity and preservation potential both change predictably with water depth. We show that the Cenomanian/Turonian faunal event in western Europe has all the predicted signatures expected if taphonomic megabias was the cause. Grade taxa terminating in pseudoextinction and Lazarus taxa are predominantly found in the onshore facies that disappear for extended periods from the rock record. Before other mass extinctions are taken at face value, a much more careful analysis of biases in the rock record needs to be carried out, and faunal disappearances need to be analyzed within a phylogenetic framework.

The function of lunules in sand dollars is reviewed and it is argued that ambulacral lunules and the anal lunule evolved for quite different purposes. Whereas ambulacral lunules evolved to increase the perimeter of the test for food gathering, this was clearly not the original function of the anal lunule, although in some genera it has become secondarily adapted to this role. Many of the unique features of the anal lunule can be explained if it evolved as an outlet for ciliary feeding currents drawn centripetally into the mouth, without disrupting either oral or aboral currents. This allowed the entire margin of the test to be used for collecting the fine particles sieved through the aboral spine canopy. Anal lunules probably evolved only once, in the Miocene, and the Monophorasteridae and Mellitidae are probably sister groups.

Clypeasteroid echinoids are a familiar and easily defined clade with a cryptic origin. They first appear in the late Paleocene and are believed to have arisen from cassiduloid ancestry, but identifying sister-group relationships more precisely has proved difficult. Two factors are responsible for this problem, the extreme morphological conservatism of cassiduloids, which has given rise to high levels of character exhaustion, and the origin of crown-group clypeasteroids through paedomorphosis. Previous analyses, based on extant representatives alone or including all Mesozoic to Recent genera, have proved unsatisfactory.

Here a parsimony analysis is undertaken using a restricted set of all stem-group clypeasteroids and cassiduloid taxa that existed immediately prior to the appearance of crown-group clypeasteroids. Inclusion of Togocyamus, the fossil taxon lying closest to the origin of crown-group clypeasteroids, is phylogenetically uninformative because that taxon is highly paedomorphic and has only generalized juvenile characteristics. However, earlier stem-group plesions provide critical data that identify Apatopygidae as extant sister group to the Clypeasteroida. Stratigraphically restricted analyses cannot eradicate the problems that arise from character exhaustion, but can minimize these with respect to specific phylogenetic questions.

Four independent lines of evidence, (1) the quality of specimen preservation, (2) taxonomic collection curves, (3) molecular divergence estimates, and (4) ghost lineage analysis of a genus-level cladogram, point to echinoids having a much poorer fossil record in the Triassic than in the Lower Jurassic. Furthermore, preservational differences between Triassic and Lower Jurassic echinoids have remained a consistent feature over 160 years of discovery. Differences exist in how effectively paleontologists have collected the fauna from available outcrops in the Triassic and Lower Jurassic. Collection curves suggest that rocks have been more efficiently searched for their fossils in Europe than elsewhere in the world, and that Lower Jurassic faunas are better sampled from available outcrop than Triassic faunas. The discovery of Triassic taxa has quickened in pace over the past 4 decades (though largely driven by a single Lagerstätte—the St. Cassian beds) while discoveries of new taxa from the Lower Jurassic have slowed. Molecular analysis of extant families and ghost lineage analysis of Triassic and Lower Jurassic genera both point to poorer sampling of Triassic faunas. This difference in the quality of the fossil record may be partially explained by differences in rock outcrop area, as marine sedimentary rocks are much less common in the Triassic than in the Lower Jurassic. However, improving biomechanical design of the echinoid test over this critical time interval was probably as important, and better explains observed preservational trends. Changes in the quality of the echinoid fossil record were thus driven as much by intrinsic biological factors as by sampling patterns.