‘The vain speculation disillusioned by the sense’: the Italian painter Agostino Scilla (1629–1700) called ‘The Discoloured’, and the correct interpretation of fossils as ‘lithified organisms’ that once lived in the sea

The search for the true nature and origin of fossils gave rise, starting about the beginning of the sixteenth century and throughout the seventeenth century, to a heated debate between the supporters of the inorganic nature of these objects and proponents of an interpretation of fossils as ex-vivi. Among the latter, a key figure is the Italian painter Agostino Scilla (1629–1700), who represents one of the first naturalists who was able to accumulate substantial evidence to support the interpretation of fossils as once-living marine organisms. The world view of Scilla and his real contribution to paleontology are here analysed and contextualised, taking into account the state of knowledge characterising the time of his activities. Scilla was not only a pioneer in the field of paleontology, but he prepared the groundwork for the achievement of milestone geological concepts such as actualism, taphonomy and recognition of internal and external moulds (in the instance of non-representation of original hard parts); Scilla deserves further recognition as one of the first to attempt sedimentological interpretation of rocky bodies observed directly in the field.     

The theory of the Earth of the Barnabite cleric Ermenegildo Pini: a mostly unknown Italian catastrophist

At the turn of the seventeenth and nineteenth centuries, Earth sciences were in a period of heated debates, with an arduous acquisition of basic principles for geology. Among the unresolved debates, was the well-known between Neptunists and Plutonists, and there was still disagreement between the supporters of a catastrophic flood and a long permanence of the sea in areas currently occupied by emerged lands. In such a climate of uncertainty appears the ‘Theory of the Earth’ of Ermenegildo Pini, an Italian Barnabite cleric. Pini was a many-faceted figure, including naturalist-scientist and technician, with interests ranging from architecture and engineering to natural sciences sensu lato. As a Diluvialist and a Neptunist, Pini strongly rejected the igneous theory – with Earth completely molten in origin – preferring instead one involving a fluidity in water and formation of ‘primary mountains’ due of centrifugal acceleration induced by Earth’s rotation. Alternatively, the so-called ‘transitional’ and ‘secondary’ mountains were entirely attributed to the rapid, catastrophic and universal flood literally interpreted from the Holy Scriptures. Despite his strongly theistic approach to the evolution of our planet, some of the intuitions and methodological approaches of Pini are extremely interesting and worthy of review and renewed discussion.     

ACOUSTIC IDENTIFICATION OF NINE DELPHINID SPECIES IN THE EASTERN TROPICAL PACIFIC OCEAN

Acoustic methods may improve the ability to identify cetacean species during shipboard surveys. Whistles were recorded from nine odontocete species in the eastern tropical Pacific to determine how reliably these vocalizations can be classified to species based on simple spectrographic measurements. Twelve variables were measured from each whistle ( n = 908). Parametric multivariate discriminant function analysis (DFA) correctly classified 41.1% of whistles to species. Non-parametric classification and regression tree (CART) analysis resulted in 51.4% correct classification. Striped dolphin whistles were most difficult to classify. Whistles of bottlenose dolphins, false killer whales, and pilot whales were most distinctive. Correct classification scores may be improved by adding prior probabilities that reflect species distribution to classification models, by measuring alternative whistle variables, using alternative classification techniques, and by localizing vocalizing dolphins when collecting data for classification models.     

Site fidelity and association patterns in a deep-water dolphin: Rough-toothed dolphins (Steno bredanensis) in the Hawaiian Archipelago

In the Pacific, rough-toothed dolphins ( Steno bredanensis ) are typically found in the open ocean and in deep waters around oceanic islands. We examined habitat use, site fidelity, movements, and association patterns of this species in the main Hawaiian Islands. Sighting rates were highest in depths >1,500 m. There were frequent within- and between-year resightings off the island of Hawai'i, indicating a small population size with high site fidelity. Resighting rates were lower off Kaua'i/Ni'ihau, indicating a larger population size, but with some site fidelity. Two individuals were documented moving from Kaua'i to Hawai'i, a distance of 480 km, but were not seen to associate with dolphins off Hawai'i. Observed movements were consistent with at most 2% dispersal per year between these two areas. Differences in group sizes, habitat use, and behavior imply that movements among the islands may be limited. Little is known about the diet of rough-toothed dolphins in Hawai'i, but they are thought to feed primarily on near-surface species. High fidelity to deep-water areas off the island of Hawai'i likely reflects an increase in the predictability of prey associated with upwelling due to the island mass effect, wind stress curl and cyclonic eddies that form off the island.     

Shallow-water habitat use and population parameters of rough-toothed dolphins,Steno bredanensis (G. Cuvier in Lesson, 1828) in southeastern Brazil

The rough-toothed dolphin (Steno bredanensis) is a poorly known species along its distribution especially in the Southern Hemisphere where data on habitat use and population parameters are scarce. Boat-based surveys were conducted from 2009 to 2017 in a shallow water environment in southeastern Brazil. During focal-group observations, S. bredanensis was more commonly found in mean depths of 22 m with varying group size and composition. Generalized additive models showed that group size was influenced by environmental variables such as sea surface and bottom temperatures, depth, and season. Photo-identification effort allowed us to catalogue 173 well-distinct marked individuals. Estimates of population parameters showed high and constant survival (Φ = 0.99) corroborating site fidelity but time varying capture probabilities (p = .03–.71). An open population model also indicated a small abundance estimate (Nt = 218) of S. bredanensis in the study area, improving knowledge for this species in shallow water environments of the southwestern Atlantic Ocean.     

Diel and lunar variation in diving behavior of rough-toothed dolphins (Steno bredanensis) off Kauaʻi,Hawaiʻi

Observational studies describe rough-toothed dolphins (Steno bredanensis) actively foraging during the day on epipelagic species. Using data from depth-transmitting satellite tags deployed on nine individuals off Kauaʻi, we investigated diving behavior and the effects of lunar phase and solar light levels on vertical movements. Overall, tagged rough-toothed dolphins primarily used near-surface waters, spending between 83.6% and 93.7% of their time in the top 30 m of the water column. When diving, grand mean, median, and maximum dive depths were 76.9 m, 67.5 m, and 399.5 m, although individuals were in water with depths from approximately 700–1,450 m. Dive rates varied by time of day, being lowest during the day and at dawn and highest at dusk and night. Dives were deepest (M = 133.7 m, SD = 52.6 m, median = 106.5 m) and longest (M = 4.0 min, SD = 0.4 min, median = 4.0 min) at dusk, suggesting dolphins were taking advantage of prey rising to the surface in response to reduced light levels. Lunar phase indirectly affected diving, with deeper and longer dives occurring with increasing illumination. The variations in dive behavior across solar and lunar cycles indicate diving patterns shift based on the distribution of prey.