Classifying organisms and artefacts by their outline shapes

We often wish to classify objects by their shapes. Indeed, the study of shapes is an important part of many scientific fields, such as evolutionary biology, structural biology, image processing and archaeology. However, mathematical shape spaces are rather complicated and nonlinear. The most widely used methods of shape analysis, geometric morphometrics, treat the shapes as sets of points. Diffeomorphic methods consider the underlying curve rather than points, but have rarely been applied to real-world problems. Using a machine classifier, we tested the ability of several of these methods to describe and classify the shapes of a variety of organic and man-made objects. We find that one method, based on square-root velocity functions (SRVFs), outperforms all others, including a standard geometric morphometric method (eigenshapes), and that it is also superior to human experts using shape alone. When the SRVF approach is constrained to take account of homologous landmarks it can accurately classify objects of very different shapes. The SRVF method identifies a shortest path between shapes, and we show that this can be used to estimate the shapes of intermediate steps in evolutionary series. Diffeomorphic shape analysis methods, we conclude, now provide practical and effective solutions to many shape description and classification problems in the natural and human sciences.</p

Greek vases as media of communication: The Epeleios painter and his companions

Athenian vase-painters endeavoured to produce scenes which appealed to as many different customers as possible. The Epeleios Painter and his circle decorated mainly cups in the early 5th century BC. Beazley derided their paintings as Schmiererei, but their vases nevertheless attracted buyers on the shores of the Black Sea, in Thasos, Athens, where their cups were dedicated on the Acropolis and used in the Agora, Etruria, and perhaps beyond, since repairs on a cup fragment once on the Roman art market suggest that it was bought by a prince of the Hallstatt culture. The appeal of the workshop’s cups lay in the shape, which suggested that the owner was part of the symposium class, and the relentlessly cheerful scenes of symposia, komasts, athletes, and warriors, which implied a Greek aristocratic lifestyle too. A few of the mythological scenes appear to have a special Athenian flavour as they juxtapose the hero of the Archaic period, Herakles, with the new hero of the democratic age, Theseus, but both would have been popular choices for Etruscan graves because they personified exemplary lives and both escaped death Numerous inscriptions, some just scribbled words, some proper kalos inscriptions, must have added to the attraction overseas as a second sophisticated layer of decoration, especially in Etruria: all the workshop’s vessels praising Athenians by name have been found there and probably identified the buyers as cultured individuals partaking in Greek culture. The named males, just like the individual styles, show that the Epeleios Painter and his fellows were closely linked to other Athenian cup painters of the period.</p

A Son of Nikon or Nikon Victorious: A New Inscription on a Fragment of a Pseudo Panathenaic Amphora

Recently, an inscribed fragment of a closed vase made of buff pinkish clay, covered with a red-orange wash, 11.8 cm wide and 8.4 cm high, and decorated with black, lustrous clay-paint surfaced briefly on the Swiss art market. It preserves a small section of the black tongue pattern on the shoulder and a wide black strip separating ornament and a panel with a straight glossy black line angled upwards; and the incomplete inscription TONIKONO[… . This paper endeavours to place the inscription and the name Nikon in a wider context and to examine the use of Pseudo-Panathenaic Amphorae

The good, the bad, and the misleading. A network of names on (mainly) Athenian vases

The earliest Greek inscriptions are incised graffiti on geometric pottery from around the middle of the 8th century. They were usually inscribed by their owners some time after the purchase. A late geometric oinochoe found in Athens1 was presented as a prize in a dancing competition and bears the incised inscription HOΣ ΝYΝ OΡΧΕΣΤÔΝ ΠΆΝΤΟΝ AΤΑΛΌΤΑΤΑ ΠΑΊΖΕΙ, ΤÔ ΤΌΔΕ ΚΛ[.]ΜΙΝ[...], “Whoever of all these dancers now plays most delicately, to him this ...” on the black shoulder. Other vases name their owners, one of whom was clearly worried to lose a prize possession since he wrote “I am the cup of Hakesandros … whoever steals me … will lose his eyesight” on a late geometric cup excavated in Methone2. Sir John Boardman donated an Attic late geometric fragment from Al Mina with an incised graffito …]ναβεο[… to the Ashmolean Museum in Oxford3. A late geometric Euboean skyphos, found in Pithekoussai4 and usually dated 740/720, preseves the first reference to the works of Homer: “ΝΈΣΤΟΡΟΣ [....] ΕΠΟΤ[ΟΝ] ΠΟΤΉΡΙΟ[Ν] OΣ Δ’ AΝ ΤΟYΔΕ Π[ΊΗΣΙ] ΠΟΤΗΡΊ[ΟΥ] ΑYΤΊΚΑ ΚHΝΟΝ HIΜΕΡ[ΟΣ ΑIΡ]ΉΣΕΙ ΚΑΛΛΙΣΤ[ΕΦΆΝ]ΟΥ ἈΦΡΟΔΊΤΗΣ”

Two new Lekythoi and two ’Ghosts’

Most archaeologists agree that the antiquities market is ‘a bad thing’ since vases appear bereft of their context, are frequently purloined from ancient graves, and their high prices encourage illicit dealings. A few antiquaries opine that such vessels are still useful, because they often provide their own context, are evidence of workshop outputs, and give chronological, artistic, and iconographical information. In earlier times, such vases were published in basic or lavish catalogues held in university libraries, and thus permanently documented. The success of the internet as a sales platform means that ancient pots, ‘important’ and otherwise, appear briefly and disappear as quickly without a trace. One such vessel, a black pattern lekythos, is the subject of this article