What can we learn about ecology and evolution from the fossil record?

The increased application of abundance data embedded within a more detailed and precise environmental context is enabling paleontologists to explore more rigorously the dynamics and underlying processes of ecological and evolutionary change in deep time. Several recent findings are of special theoretical interest. Community membership is commonly more stable and persistent than expected by chance, even in the face of the extreme environmental changes of the Ice Ages, and major evolutionary novelties commonly lie dormant for tens of millions of years before the ecological explosions of the clades that possess them. As we discuss here, questions such as these cannot be adequately addressed without the use of the fossil record.     

Can we detect a west Norwegian tree line from modern samples of plant remains and pollen? Results from the DOORMAT project

In the DOORMAT (Direct Observation of Recent Macrofossils Across Treeline) project, the modern representation of local vegetation by pollen and plant remains (plant macrofossils) across a west Norwegian tree line, composed of Betula pubescens and Pinus sylvestris, has been studied over 2 years. The aim was to discover if the modern tree line could be detected and therefore how precisely past tree-line movements could be reconstructed and related to Holocene climate changes by using one proxy or a combination of both. Traps were placed in the vegetation from 663 to 1,120 m a.s.l., spanning the pine altitudinal species limit, the birch tree-line ecotone, and the vegetation zones up to the mid-alpine zone. Three traps were also set in the small lake Trettetjørn close to the modern tree line at 800 m a.s.l. Traps were emptied twice a year to sample both summer and winter seasons. Macrofossils represent their local vegetation well. However, tree Betula remains were trapped above the tree line and Pinus and Picea remains were recorded 1.0–1.5 km away from their sources, demonstrating considerable dispersal capacity. This shows that rare macrofossil remains do not necessarily represent the local presence of these trees. Aerial tree pollen deposition in traps at the upper limit of pine woodland and in the subalpine birch woodland was unexpectedly low, whereas pollen accumulation rates (PAR) were orders of magnitude higher in the lake traps. We hypothesise that the lake receives regional pollen rain washed in from its catchment by snow meltwater and that high values in traps are due to continuous suspension of pollen in the lake water during summer. The interpretation of tree-line changes from existing Holocene pollen and plant macrofossil data from Trettetjørn was supported and refined by the DOORMAT macrofossil data, but the modern pollen data were anomalous.     

Can we predict centres of plant species richness and rarity from environmental variables in sub‐Saharan Africa?

In order to investigate continental-scale patterns of plant species richness and rarity, distribution maps of 3661 plant species were digitized into a one degree grid of sub-Saharan Africa using the WORLDMAP computer programme. Cells with high species richness were also likely to be those containing the greatest number of species of restricted range, but areas such as the South African Cape and the Eastern Arc mountains were found to have more restricted-range species than predicted from their richness scores. The two environmental predictors which had the strongest individual relationships with both species richness and range-size rarity were absolute maximum annual temperature and mean monthly potential evapotranspiration. However, correlative predictive powers of these variables were low, with R =−0.58 and R =−0.54, respectively ( P  < 0.01). Multiple regression also failed to produce a strong explanatory model for observed continental-scale patterns of diversity. Spatial variability analysis showed that this was likely to be because different environmental parameters predicted different centres of richness and rarity. West African species richness was better predicted by absolute maximum annual temperature, whereas East African species richness was better predicted by mean monthly potential evapotranspiration.  © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society , 2003, 142 , 187–197.     

Middle phalanx skeletal morphology in the hand: Can it predict flexor tendon size and attachments?

Specific sites on the palmar diaphysis of the manual middle phalanges provide attachment for the flexor digitorum superficialis (FDS) tendon. It has been assumed in the literature that lateral palmar fossae on these bones reflect locations for these attachments and offer evidence for relative size of the flexor tendon. This assumption has led to predictions about relative FDS muscle force potential from sizes of fossae on fossil hominin middle phalanges. Inferences about locomotor capabilities of fossil hominins in turn have been drawn from the predicted force potential of the flexor muscle. The study reported here provides a critical first step in evaluating hypotheses about behavioral implications of middle phalangeal morphology in fossil hominins, by testing the hypothesis that the lateral fossae reflect the size of the FDS tendon and the location of the terminal FDS tendon attachments on the middle phalanx. The middle phalangeal region was dissected in 43 individuals from 16 primate genera, including humans. Qualitative observations were made of tendon attachment locations relative to the lateral fossae. Length measurements of the fossae were tested as predictors of FDS tendon cross-sectional area and of FDS attachment tendon lengths. Our results lead to the conclusion that the hypothesis must be rejected, and that future attention should focus on functional implications of the palmar median bar associated with the lateral fossae.     

Can we bring Madagascar's critically endangered palms back from the brink? Genetics,ecology and conservation of the critically endangered palm Beccariophoenix madagascariensis

Madagascar has a highly distinctive flora and is one of the world biodiversity hot spots. There are more than 170 species of palms, the majority of which are vulnerable, endangered or critically endangered endemics. Palms are utilized for many human uses, many of which lead to plant death or seed harvesting. Combined with reduced populations resulting from extensive forest clearing, those species which are harvested from the wild are under additional threat of extinction. Species recovery programmes have the potential to save some of the most iconic species before it is too late. This study documented the current known populations of the critically endangered palm Beccariophoenix madagascariensis, a species utilized for both local and international purposes. The study specifically investigated the genetic diversity and inbreeding within populations and the potential differentiation between populations and with the newly described species B. alfredii . We found that despite critically small population sizes there was considerable genetic diversity within populations. We also found that ecologically and or geographically distinct populations were genetically distinct. Populations within 3 km of each other exhibited considerable gene flow, probably owing to seed dispersal. The populations were inbred but reproductive viability had been maintained. Conservation and recovery options are discussed. © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 154 , 589–608.     

Can we predict carbon stocks in tropical ecosystems from tree diversity? Comparing species and functional diversity in a plantation and a natural forest

? Linking tree diversity to carbon storage can provide further motivation to conserve tropical forests and to design carbon-enriched plantations. Here, we examine the role of tree diversity and functional traits in determining carbon storage in a mixed-species plantation and in a natural tropical forest in Panama. ? We used species richness, functional trait diversity, species dominance and functional trait dominance to predict tree carbon storage across these two forests. Then we compared the species ranking based on wood density, maximum diameter, maximum height, and leaf mass per area (LMA) between sites to reveal how these values changed between different forests. ? Increased species richness, a higher proportion of nitrogen fixers and species with low LMA increased carbon storage in the mixed-species plantation, while a higher proportion of large trees and species with high LMA increased tree carbon storage in the natural forest. Furthermore, we found that tree species varied greatly in their absolute and relative values between study sites. ? Different results in different forests mean that we cannot easily predict carbon storage capacity in natural forests using data from experimental plantations. Managers should be cautious when applying functional traits measured in natural populations in the design of carbon-enriched plantations.     

Can we consider the stocks of alfonsinos Beryx splendens and Beryx decadactylus from the Azores a discrete fishery management unit?

This paper summarises the detailed information on catch, fork length, weight, sex and maturity of alfonsinos Beryx splendens and Beryx decadactylus collected from targeted surveys in Azores waters, complemented by fishery data, over the past c. 20 years. To date, it was not possible to define if the Azorean component of the population can be considered as a discrete local management unit. The reason for this is the lack of available information for these resources covering the entire spatial distribution of the species in the North Atlantic Ocean. Additionally, there are some conflicts between the different genetic results available, poor understanding about the species movements and data from the Azores show some discrepancies in aspects of reproduction. Consequently, there is no analytical assessment for this resource and the stock of Beryx spp. is currently managed based on the precautionary approach. Outputs of recent analyses are presented in this study and possible assumptions and strategies for the assessment are discussed.     

Maps, codes, and sequence elements: can we predict the protein output from an alternatively spliced locus?

Alternative splicing choices are governed by splicing regulatory protein interactions with splicing silencer and enhancer elements present in the pre-mRNA. However, the prediction of these choices from genomic sequence is difficult, in part because the regulators can act as either enhancers or silencers. A recent study describes how for a particular neuronal splicing regulatory protein, Nova, the location of its binding sites is highly predictive of the protein's effect on an exon's splicing.     

Reflections on the tissue kallikrein and kallikrein-related peptidase family - from mice to men - what have we learnt in the last two decades?

The genes encoding the kininogenase, glandular tissue kallikrein, in rodents and man were first described in the mid-1980s. Remarkably, they appeared to be part of a much larger highly conserved family of genes (GK) in rodents, but only had two paralogs in man. This discrepancy was not rectified until the late 1990s/2000 with the identification of a cluster of 12 more kallikrein-related (KLK) genes in the human 19q13 locus and the subsequent identification of their rodent homologs. Interestingly, there are remarkable similarities in expression patterns, hormonal regulation and functional attributes of the old (GK) and new (KLK) families which underscore the evolutionary conservation across these loci and species. This historical perspective focuses on the lessons learned from earlier studies on the rodent GK gene families and the striking similarities of some attributes, yet uniqueness, of others. These earlier findings have all contributed to the current status of the KLK serine peptidase-encoding gene family as an exciting source of new biomarkers and therapeutic targets.     

Lignicolous freshwater fungi along a north–south latitudinal gradient in the Asian/Australian region; can we predict the impact of global warming on biodiversity and function?

Fungi play a key role in decomposition of submerged wood in streams, breaking down lignocelluloses and releasing nutrients, and are important in ecosystem functioning. These wood decay fungi are known as freshwater lignicolous fungi and are usually studied by collecting submerged woody litter, followed by incubation in a moist chamber. This review explains what are freshwater lignicolous fungi, their decay mechanisms, roles and physiological attributes. Asian/Australasian lignicolous freshwater fungi have been relatively well-surveyed and enable an account of their distribution along a latitudinal transect. Unlike freshwater leaf-dwelling fungi their diversity in water bodies is greater towards the Equator which suggests they are important for decaying submerged wood in the tropics. Riparian vegetation, disturbances such as pollution, streams drying and study methods, may all affect the diversity of freshwater lignicolous fungi, however, the overall trend is a higher diversity in the tropics and subtropics. Climate changes together with increasing deposition of woody debris from human activities, and alteration of environmental factors (such as water pollution, and dam building) will impact freshwater lignicolous fungi. Changing diversity, structure and activities of freshwater fungal communities can be expected, which will significantly impact on aquatic ecosystems, particularly on nutrient and carbon cycles. There is a great opportunity to monitor changes in freshwater fungi communities along latitudinal (north to south) and habitat gradients (from human disturbed to natural habitats), and study ecological thresholds and consequences of such changes, particularly its feedback on nutrient and carbon cycles in freshwater systems.