Do the evolutionary interactions between moths and bats promote niche partitioning between bats and birds?

Ecological theory suggests that the coexistence of species is promoted by the partitioning of available resources, as in dietary niche partitioning where predators partition prey. Yet, the mechanisms underlying dietary niche partitioning are not always clear. We used fecal DNA metabarcoding to investigate the diets of seven nocturnal insectivorous bird and bat species. Low diet overlap (2%–22%) supported resource partitioning among all species. Differences in diet corresponded with species identity, prey detection method, and foraging behavior of predators. Insects with ultrasonic hearing capabilities were consumed significantly more often by birds than bats, consistent with an evolved avoidance of echolocating strategies. In turn, bats consumed a greater proportion of noneared insects such as spruce budworms. Overall, our results suggest that evolutionary interactions among bats and moths translate to dietary niche partitioning and coexistence among bats and nocturnal birds.     

What will result from the interaction between functional and evolutionary biology?

The modern synthesis has been considered to be wrongly called a "synthesis", since it had completely excluded embryology, and many other disciplines. The recent developments of Evo-Devo have been seen as a step in the right direction, as complementing the modern synthesis, and probably leading to a "new synthesis". My argument is that the absence of embryology from the modern synthesis was the visible sign of a more profound lack: the absence of functional biology in the evolutionary synthesis. I will consider the reasons for this absence, as well as the recent transformations which favoured a closer interaction between these two branches of biology. Then I will describe two examples of recent work in which functional and evolutionary questioning were tightly linked. The most significant part of the paper will be devoted to the transformation of evolutionary theory that can be expected from this encounter: a deep transformation, or simply an experimental confirmation of this theory? I will not choose between these two different possibilities, but will discuss some of the difficulties which make the choice problematic.     

Are the oldest ‘fossils’, fossils?

A comparative statistical study has been carried out on populations of modern algae, of Precambrian algal microfossils, of the organized elements of the Orgueil carbonaceous meteorite, and of the oldest microfossil-like objects now known (spheroidal bodies from the Fig Tree and Onverwacht Groups of the Swaziland Supergroup, South Africa). The distribution patterns exhibited by the >3000 m.y.-old Swaziland microstructures bear considerable resemblance to those of the abiotic organized elements but rather markedly differ from those exhibited by younger, assuredly biogenic, populations. Based on these comparisons it is concluded that the Swaziland spheroids could be, at least in part, of non-biologic origin; these oldest known fossil-like micro-structures should not be regarded as constituting firm evidence of Archean life.Given at the International Seminar Origin of Life, 2–7 August 1974, Moscow, U.S.S.R.     

The late Neandertal supraorbital fossils from Vindija Cave,Croatia: a biased sample?

The late Neandertal sample from Vindija (Croatia) has been described as transitional between the earlier Central European Neandertals from Krapina (Croatia) and modern humans. However, the morphological differences indicating this transition may rather be the result of different sex and/or age compositions between the samples. This study tests the hypothesis that the metric differences between the Krapina and Vindija supraorbital samples are due to sampling bias. We focus upon the supraorbital region because past studies have posited this region as particularly indicative of the Vindija sample's transitional nature. Furthermore, the supraorbital region varies significantly with both age and sex.We analyzed four chords and two derived indices of supraorbital torus form as defined by Smith & Ranyard (1980, Am. J. phys. Anthrop.93, pp. 589-610). For each variable, we analyzed relative sample bias of the Krapina and Vindija samples using three sampling methods. In order to test the hypothesis that the Vindija sample contains an over-representation of females and/or young while the Krapina sample is normal or also female/young biased, we determined the probability of drawing a sample of the same size as and with a mean equal to or less than Vindija's from a Krapina-based population. In order to test the hypothesis that the Vindija sample is female/young biased while the Krapina sample is male/old biased, we determined the probability of drawing a sample of the same size as and with a mean equal or less than Vindija's from a generated population whose mean is halfway between Krapina's and Vindija's. Finally, in order to test the hypothesis that the Vindija sample is normal while the Krapina sample contains an over-representation of males and/or old, we determined the probability of drawing a sample of the same size as and with a mean equal to or greater than Krapina's from a Vindija-based population. Unless we assume that the Vindija sample is female/young and the Krapina sample is male/old biased, our results falsify the hypothesis that the metric differences between the Krapina and Vindija samples are due to sample bias.     

Why are there so few evolutionary transitions between aquatic and terrestrial ecosystems?

Insects and flowering plants have rarely invaded the sea. Explanations for this have traditionally centered on the unique shortcomings of these groups in the marine environment. We show, however, that transitions among terrestrial, freshwater, and marine environments are infrequent in all major plant and animal clades except tetrapod vertebrates. In general, well-adapted incumbents are at a competitive advantage over would-be invaders from a physically different habitat. Data on the times and places of transition are consistent with our contention that evolutionary transitions among physically different environments are most likely when incumbents in the recipient environment exist in a regime of low-intensity competition and prcdation, as in terrestrial communities of the middle Paleozoic or the land biotas of oceanic islands. Freshwater environments, in which inferred intensities of predation are lower than in most marine and terrestrial environments, offer less biotic resistance to invaders than do communities in the sea or on land. Most invaders respond to novel physical circumstances by shutting down their metabolic machinery, and therefore add to their subordinate status as competitors with active incumbents. Only active tetrapods, particularly those with high and endothermically driven rates of metabolism, have successfully overcome this limitation.     

What was the evolutionary synthesis?

There has not been another scientific revolution that caused as much turmoil and dissension as the darwinian one. For almost 80 years it was again and again pronounced to be a failure and to be totally refuted, and at least three major alternatives were proposed to replace it. Yet, in the 1930s-1940s the opposing views were quickly and decisively refuted and a largely unified evolutionary theory emerged. Why and how this happened, however, is still rather controversial.     

Pancreatic lipases: evolutionary intermediates in a positional change of catalytic carboxylates?

Comparison of the fold of lipases from Geotrichum candidum and from human pancreas identified a high degree of similarity which was not expected on the basis of their amino acid sequences. Although both enzymes utilize a serine protease-like catalytic triad, they differ in the topological position of the acid. We speculate that these proteins are evolutionarily related and that the pancreatic lipase is an evolutionary intermediate in the pathway of migration of the catalytic acid to a new position within the fold.     

Neandertal knees: power lifters in the Pleistocene?

It has been proposed (Trinkaus, 1983 a; Miller & Gross, 1998) that the marked thickness of Neandertal patellae and/or the posterior displacement of their tibial condyles increased their relative M. quadriceps femoris moment arms, thereby making their legs powerful in extension. However, it is necessary to compare these reflections of muscle moment arm length to appropriate measures of the body weight moment arm and body mass estimates, both of which are influenced by ecogeographically determined body proportions. Reassessment of tibial condylar displacement and patellar thickness, as well as patellar height, relative to an appropriate measure of the moment arm for the baseline load on the knee (body weight), to that moment arm times estimated body mass, and to that moment arm times a skeletal reflection of body mass (femoral head diameter) rejects the hypothesis that the Neandertals had exceptionally powerful knee extension. Relative tibial condylar displacement remains above that of a modern industrial society sample, but similar to that of the Broken Hill tibia, Late Pleistocene early modern humans and a recent human nonindustrial sample. Relative patellar thickness is similar to that of early modern humans, who have relatively thick patellae compared to the late Holocene human samples. Consequently, once body proportions are taken into account, there is little difference between the Neandertals and other later Pleistocene humans in knee extensor mechanical advantage, and all of these fossil hominids are similar in the more important proximal tibial proportions to those of nonindustrial recent humans.     

Were Gram-positive rods the first bacteria?

At some point in the evolution of life, the domain Bacteria arose from prokaryotic progenitors. The cell that gave rise to the first bacterium has been given the name (among several other names) "last universal ancestor (LUA)". This cell had an extensive, well-developed suite of biochemical strategies that increased its ability to grow. The first bacterium is thought to have acquired a covering, called a sacculus or exoskeleton, that made it stress-resistant. This protected it from rupturing as a result of turgor pressure stress arising from the success of its metabolic abilities. So what were the properties of this cell's wall? Was it Gram-positive or Gram-negative? And was it a coccus or a rod?     

Is there an evolutionary relationship between WARP (von Willebrand factor A-domain-related protein) and the FACIT and FACIT-like collagens?

We suggest that there is an evolutionary relationship between von Willebrand factor A-domain-related protein (WARP), and the fibril-associated collagen with interrupted triple helix (FACIT) and FACIT-like subfamilies of collagens. Data from a comparison of amino acid sequences, domain organisation and chromosomal location are consistent with the hypothesis that WARP and these collagens share a common collagen ancestor. In support of this is the observation that the WARP 3' coding region is GC-rich suggesting that this may represent the remnant of a triple helix protein domain which WARP has 'lost' during evolution.     

Interactions between Papilionidae and ancient Australian Angiosperms: evolutionary specialization or ecological monophagy?

The evolution of host range for insect herbivores involves many behavioral, physiological, and biochemical adaptations that often lead to locally specialized populations or species. Such specialization may be constrained by ecological factors (e.g., local host availability) or by evolutionary factors (e.g., phylogenetic divergence in behavioral, physiological, or biochemical detoxification enzymes; and potential inabilities to return to ancestral hosts). While insect adaptations to new hosts can be rapid, ancient detoxification systems may persist in some lineages of swallowtail butterflies (Papilionidae) for millions of years. Here, we test various species of specialized species/populations of Papilionidae (Lepidoptera) from North America and from Australia on an array of Australian host plant families in order to determine whether the current feeding constraints reflect loss of capabilities to recognize and use hosts other than their current (local) favorites. We selected two species of Lauraceae specialists (Papilio troilus L. and Papilio palamedes Drury) from North America and one locally specialized population of Papilio glaucus L. that only uses one plant species in the Magnoliaceae in Florida. We also examined three species/populations of Australian swallowtails for comparison, including the Monimiaceae‐specialized Graphium macleayanum moggana L. E. Couchman, the Rutaceae‐specialized Papilio aegeus Donovan, and the Annonaceae‐specialized Graphium eurypylus L. Our aim was to determine whether neonate larvae of these six specialists could survive on any plants other than their currently favored species. While the Lauraceae specialists could use nothing else and were thus evolutionarily constrained, the Magnoliaceae‐, Rutaceae‐, and Monimiaceae specialists all had common abilities to accept, feed, and grow on plants in the Lauraceae, Monimiaceae, Magnoliaceae, and Rutaceae families. Even the Annonaceae specialist was discovered using Magnoliaceae in the field, suggesting existence here also of both flexiblity in preferences and detoxification abilities and ‘ecological monophagy’.     

A carnivorous niche for Java Man? A preliminary consideration of the abundance of fossils in Middle Pleistocene Java

Considering anatomical and archaeological aspects of Homo erectus, it is likely that meat of vertebrates was an important part in its diet. Unfortunately, no or hardly any information is available for Java Man (Homo erectus). Therefore, in this paper, the Number of Identified Specimens (NISP) of five Middle Pleistocene Javanese sites are examined, and the Minimum Number of Individuals (MNI) from two of them are calculated, to acquire information about the possible ecological role of Javanese Homo erectus. Although one has to be extremely careful with the interpretation of fossil bone assemblages in order to try to gain some insight about the abundance of species in palaeocommunities, it is argued that both the NISP and the MNI indicate that the bone accumulations reflect at least two trophic levels in the ecological pyramid, that of primary and secondary consumers. The occurrences of the remains of Homo erectus are comparable with the quantity of secondary consumers, i.e., large carnivores. This could suggest that this species had, as an omnivore, a carnivorous niche, in Java.