In plantation forests in parts of Europe, the tree stumps left after felling are now sometimes pulled out of the ground to supply wood fuel for biomass power stations. The stump is the base of the trunk and the attached woody roots. Tree stumps and roots are extracted using a hydraulic head on a tracked excavator or with a mechanical head equipped by a special tool for tractors. Stump harvesting is expected to provide an increasing component of the woody material required by the woody biomass power sector in Europe. (Full article...)
In plantation forests in parts of Europe, the tree stumps left after felling are now sometimes pulled out of the ground to supply wood fuel for biomass power stations. The stump is the base of the trunk and the attached woody roots. Tree stumps and roots are extracted using a hydraulic head on a tracked excavator or with a mechanical head equipped by a special tool for tractors. Stump harvesting is expected to provide an increasing component of the woody material required by the woody biomass power sector in Europe. (Full article...)
The bullhead sharks are members of the genus Heterodontus, the only members of the family Heterodontidae and only living members of the order Heterodontiformes. All are relatively small, with the largest species reaching just 1.65 metres (5.5 ft) in maximum length. They are bottom feeders in tropical and subtropical waters.
The Heterodontiforms appear in the fossil record in the Early Jurassic. The oldest fossils of the modern genus date to the Late Jurassic. Despite the very ancient origins of this genus and its abundance in the fossil record, phylogenetic evidence indicates that all extant species in the genus arose from a single common ancestor that survived the Cretaceous-Paleogene extinction, with diversification into modern species only starting around the mid-Eocene. (Full article...)
Springer's sawtail catshark (Galeus springeri) is a species of catshark, belonging to the familyScyliorhinidae, found in waters 457–699 m (1,499–2,293 ft) deep off the islands of the Antilles, from Cuba to the Leewards. A small, slim-bodied species reaching a length of 48 cm (19 in), the Springer's sawtail catshark can be identified by its color pattern of horizontal dark stripes in front of the first dorsal fin, and dark dorsal saddles behind. It is additionally characterized by the presence of saw-toothed crests, made of enlarged dermal denticles along both the dorsal and the ventral edges of the caudal fin. The Springer's sawtail catshark is oviparous. (Full article...)
{{Transclude list item excerpt|List of dams and reservoirs}}
Colbún Lake (Spanish: Lago Colbún) is a reservoir in the Maule Region in Chile, straddling the provinces of Talca (comuna of San Clemente) and Linares (comuna de Colbún). Located 48 km southeast of the city of Talca, the regional capital and 35 km northeast of the city of Linares and with an area of 5,700 hectares and a capacity of 1,490,000 m³, it is the largest artificial reservoir in Chile. The lake lies at an altitude of 440 metres above sea level.
Colbún Lake (Spanish: Lago Colbún) is a reservoir in the Maule Region in Chile, straddling the provinces of Talca (comuna of San Clemente) and Linares (comuna de Colbún). Located 48 km southeast of the city of Talca, the regional capital and 35 km northeast of the city of Linares and with an area of 5,700 hectares and a capacity of 1,490,000 m³, it is the largest artificial reservoir in Chile. The lake lies at an altitude of 440 metres above sea level.
The Highlands Highway passes over the Yonki Dam embankment. The adjacent Yonki villages support the operation of the dam and power station. (Full article...)
The Highlands Highway passes over the Yonki Dam embankment. The adjacent Yonki villages support the operation of the dam and power station. (Full article...)
John RayFRS (29 November 1627 – 17 January 1705) was a ChristianEnglishnaturalist widely regarded as one of the earliest of the English parson-naturalists. Until 1670, he wrote his name as John Wray. From then on, he used 'Ray', after "having ascertained that such had been the practice of his family before him". He published important works on botany, zoology, and natural theology. His classification of plants in his Historia Plantarum, was an important step towards modern taxonomy. Ray rejected the system of dichotomous division by which species were classified by repeated sub-division into groups according to a pre-conceived series of characteristics they have or have not, and instead classified plants according to similarities and differences that emerged from observation. He was among the first to attempt a biological definition for the concept of species, as "a group of morphologically similar organisms arising from a common ancestor". Another significant contribution to taxonomy was his division of plants into those with two seedling leaves (dicotyledons) or only one (monocotyledons), a division used in taxonomy today. (Full article...)
John RayFRS (29 November 1627 – 17 January 1705) was a ChristianEnglishnaturalist widely regarded as one of the earliest of the English parson-naturalists. Until 1670, he wrote his name as John Wray. From then on, he used 'Ray', after "having ascertained that such had been the practice of his family before him". He published important works on botany, zoology, and natural theology. His classification of plants in his Historia Plantarum, was an important step towards modern taxonomy. Ray rejected the system of dichotomous division by which species were classified by repeated sub-division into groups according to a pre-conceived series of characteristics they have or have not, and instead classified plants according to similarities and differences that emerged from observation. He was among the first to attempt a biological definition for the concept of species, as "a group of morphologically similar organisms arising from a common ancestor". Another significant contribution to taxonomy was his division of plants into those with two seedling leaves (dicotyledons) or only one (monocotyledons), a division used in taxonomy today. (Full article...)
John RayFRS (29 November 1627 – 17 January 1705) was a ChristianEnglishnaturalist widely regarded as one of the earliest of the English parson-naturalists. Until 1670, he wrote his name as John Wray. From then on, he used 'Ray', after "having ascertained that such had been the practice of his family before him". He published important works on botany, zoology, and natural theology. His classification of plants in his Historia Plantarum, was an important step towards modern taxonomy. Ray rejected the system of dichotomous division by which species were classified by repeated sub-division into groups according to a pre-conceived series of characteristics they have or have not, and instead classified plants according to similarities and differences that emerged from observation. He was among the first to attempt a biological definition for the concept of species, as "a group of morphologically similar organisms arising from a common ancestor". Another significant contribution to taxonomy was his division of plants into those with two seedling leaves (dicotyledons) or only one (monocotyledons), a division used in taxonomy today. (Full article...)
John RayFRS (29 November 1627 – 17 January 1705) was a ChristianEnglishnaturalist widely regarded as one of the earliest of the English parson-naturalists. Until 1670, he wrote his name as John Wray. From then on, he used 'Ray', after "having ascertained that such had been the practice of his family before him". He published important works on botany, zoology, and natural theology. His classification of plants in his Historia Plantarum, was an important step towards modern taxonomy. Ray rejected the system of dichotomous division by which species were classified by repeated sub-division into groups according to a pre-conceived series of characteristics they have or have not, and instead classified plants according to similarities and differences that emerged from observation. He was among the first to attempt a biological definition for the concept of species, as "a group of morphologically similar organisms arising from a common ancestor". Another significant contribution to taxonomy was his division of plants into those with two seedling leaves (dicotyledons) or only one (monocotyledons), a division used in taxonomy today. (Full article...)
John RayFRS (29 November 1627 – 17 January 1705) was a ChristianEnglishnaturalist widely regarded as one of the earliest of the English parson-naturalists. Until 1670, he wrote his name as John Wray. From then on, he used 'Ray', after "having ascertained that such had been the practice of his family before him". He published important works on botany, zoology, and natural theology. His classification of plants in his Historia Plantarum, was an important step towards modern taxonomy. Ray rejected the system of dichotomous division by which species were classified by repeated sub-division into groups according to a pre-conceived series of characteristics they have or have not, and instead classified plants according to similarities and differences that emerged from observation. He was among the first to attempt a biological definition for the concept of species, as "a group of morphologically similar organisms arising from a common ancestor". Another significant contribution to taxonomy was his division of plants into those with two seedling leaves (dicotyledons) or only one (monocotyledons), a division used in taxonomy today. (Foobar)
John RayFRS (29 November 1627 – 17 January 1705) was a ChristianEnglishnaturalist widely regarded as one of the earliest of the English parson-naturalists. Until 1670, he wrote his name as John Wray. From then on, he used 'Ray', after "having ascertained that such had been the practice of his family before him". He published important works on botany, zoology, and natural theology. His classification of plants in his Historia Plantarum, was an important step towards modern taxonomy. Ray rejected the system of dichotomous division by which species were classified by repeated sub-division into groups according to a pre-conceived series of characteristics they have or have not, and instead classified plants according to similarities and differences that emerged from observation. He was among the first to attempt a biological definition for the concept of species, as "a group of morphologically similar organisms arising from a common ancestor". Another significant contribution to taxonomy was his division of plants into those with two seedling leaves (dicotyledons) or only one (monocotyledons), a division used in taxonomy today. (Foobar)
John RayFRS (29 November 1627 – 17 January 1705) was a ChristianEnglishnaturalist widely regarded as one of the earliest of the English parson-naturalists. Until 1670, he wrote his name as John Wray. From then on, he used 'Ray', after "having ascertained that such had been the practice of his family before him". He published important works on botany, zoology, and natural theology. His classification of plants in his Historia Plantarum, was an important step towards modern taxonomy. Ray rejected the system of dichotomous division by which species were classified by repeated sub-division into groups according to a pre-conceived series of characteristics they have or have not, and instead classified plants according to similarities and differences that emerged from observation. He was among the first to attempt a biological definition for the concept of species, as "a group of morphologically similar organisms arising from a common ancestor". Another significant contribution to taxonomy was his division of plants into those with two seedling leaves (dicotyledons) or only one (monocotyledons), a division used in taxonomy today.
John RayFRS (29 November 1627 – 17 January 1705) was a ChristianEnglishnaturalist widely regarded as one of the earliest of the English parson-naturalists. Until 1670, he wrote his name as John Wray. From then on, he used 'Ray', after "having ascertained that such had been the practice of his family before him". He published important works on botany, zoology, and natural theology. His classification of plants in his Historia Plantarum, was an important step towards modern taxonomy. Ray rejected the system of dichotomous division by which species were classified by repeated sub-division into groups according to a pre-conceived series of characteristics they have or have not, and instead classified plants according to similarities and differences that emerged from observation. He was among the first to attempt a biological definition for the concept of species, as "a group of morphologically similar organisms arising from a common ancestor". Another significant contribution to taxonomy was his division of plants into those with two seedling leaves (dicotyledons) or only one (monocotyledons), a division used in taxonomy today.