The tracking of small avian migrants has only recently become possible by the use of small light-level geolocators, allowing the reconstruction of whole migration routes, as well as timing and speed of migration and identification of wintering areas. Such information is crucial for evaluating theories about migration strategies and pinpointing critical areas for migrants of potential conservation value. Here we report data about migration in the common swift, a highly aerial and long-distance migrating species for which only limited information based on ringing recoveries about migration routes and wintering areas is available. Six individuals were successfully tracked throughout a complete migration cycle from Sweden to Africa and back. The autumn migration followed a similar route in all individuals, with an initial southward movement through Europe followed by a more southwest-bound course through Western Sahara to Sub-Saharan stopovers, before a south-eastward approach to the final wintering areas in the Congo basin. After approximately six months at wintering sites, which shifted in three of the individuals, spring migration commenced in late April towards a restricted stopover area in West Africa in all but one individual that migrated directly towards north from the wintering area. The first part of spring migration involved a crossing of the Gulf of Guinea in those individuals that visited West Africa. Spring migration was generally wind assisted within Africa, while through Europe variable or head winds were encountered. The average detour at about 50% could be explained by the existence of key feeding sites and wind patterns. The common swift adopts a mixed fly-and-forage strategy, facilitated by its favourable aerodynamic design allowing for efficient use of fuel. This strategy allowed swifts to reach average migration speeds well above 300 km/day in spring, which is higher than possible for similar sized passerines. This study demonstrates that new technology may drastically change our views about migration routes and strategies in small birds, as well as showing the unexpected use of very limited geographical areas during migration that may have important consequences for conservation strategies for migrants.
Spectacular long-distance migration has evolved repeatedly in animals enabling exploration of resources separated in time and space. In birds, these patterns are largely driven by seasonality, cost of migration, and asymmetries in competition leading most often to leapfrog migration, where northern breeding populations winter furthest to the south. Here, we show that the highly aerial common swift Apus apus, spending the nonbreeding period on the wing, instead exhibits a rarely found chain migration pattern, where the most southern breeding populations in Europe migrate to wintering areas furthest to the south in Africa, whereas the northern populations winter to the north. The swifts concentrated in three major areas in sub-Saharan Africa during the nonbreeding period, with substantial overlap of nearby breeding populations. We found that the southern breeding swifts were larger, raised more young, and arrived to the wintering areas with higher seasonal variation in greenness (Normalized
Common Swifts Apus apus have occasionally been reported roosting overnight by hanging in the foliage of trees. However, roosting in foliage, which is often associated with food shortage as a result of adverse weather, appears to be an important alternative to aerial roosting. Thirty‐nine observations of the behaviour have been recorded previously in Europe, some of them concerning two or more birds. Furthermore, each August from 1982 to 2000, within a restricted area of c. 300 × 300 m in southern Sweden, Swifts (118 total) were observed to roost in the foliage of trees or on a latticework mast, whereas others (230 total) were observed making ‘fly‐ins’ typical of the behaviour preliminary to roosting. Of those roosting, 39 Swifts could be aged, and all but one of these were newly fledged juveniles. The Swifts perched late at dusk with maximum frequency about 30 min after sunset, but tended to perch earlier in cloudy weather and later in clear weather. Numbers of roosting Swifts were correlated with low mean temperatures in August, and appearances of roosting Swifts were correlated with low local evening temperatures. During May–July 1982–2000, within the same small area, 18 Swifts were observed to roost in this manner and 29 other Swifts made preroost fly‐ins. It is concluded that the behaviour is used more frequently and is more widespread geographically than thus far published observations indicate. This applies especially to newly fledged young on their first migration. Adaptive explanations for this are suggested, with the implication that the behaviour may be widespread in swifts of the tribe Apodini.
A visual conscious experience is my empirical basis. All that we know comes to us through conscious experiences. Thanks to natural evolution, we have nearly direct perception, and can largely trust the information we attain. There is full integration, with no gaps, of organisms in the continuous world. Human conscious experiences, on the other hand, are discrete. Consciousness has certain limits for its resolution. This is illustrated by the so-called light-cone, with consequences for foundations in physics. Traditional universals are replaced by feels and distributions. Conscious experiences can be ordered within a framework of conceptual spaces. Triple Aspect Monism (TAM) can represent the dynamics of conscious systems. However, to fully represent the creative power of human consciousness, an all-inclusive view is suggested: Multi Aspect Monism (MAM).
We define precognitive affect, composed of information holding dispositional states, as noncontextual, rudimentary building blocks of subjective intentionality. We take on a psychodynamic approach to intentional agency. Intentions unfold into actions in animate thermodynamics reducing subjective uncertainty by negentropic action. They are intentions in action carrying meaning in species having complex protein interactions with various regulated gene sets. In particular, the unfolding of intentionality in terms of biological purpose introduced by subjective functioning allows for a satisfactory account of subjective intentionality. The underlying experience of acting paves the way for understanding meaning of precognitive affect from subjective functioning. Therefore, the brain’s subjective intentionality as the underlying experience of acting is embedded in a negentropic “consciousness code” of “hidden” thermodynamic energy. It is the negentropically-derived quantum potential energy in the unified functioning of brain consciousness at the macroscopic scale. While at the mesoscopic scale, Schrödinger processes create boundary conditions for negentropic action to inform the intentional agency.
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