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105-501: James Ross Island ( 64°10′S 57°45′W  /  64.167°S 57.750°W  / -64.167; -57.750  ( James Ross Island ) ) is a large island off the southeast side and near the northeastern extremity of the Antarctic Peninsula , from which it is separated by Prince Gustav Channel . Rising to 1,630 metres (5,350 ft), it is irregularly shaped and extends 40 nautical miles (74 km; 46 mi) in

210-801: A fauna distinct from that of Patagonia , and each of these distinct from that of India and Madagascar; likewise, Australia, New Zealand, and Antarctic seemed connected to the exclusion of the others. This contrasted with existing recognition of links between the flora and marine invertebrate fauna between Patagonia, Antarctica, Australia, and New Zealand, termed the Weddellian Bioprovince . The recognition of Morrosaurus and Trinisaura as Antarctic elasmarians closely related to animals from South America constituted important evidence of such ties between these continents existing in dinosaurs as well. This would be bolstered by later studies producing firmer evidence of Australian ornithopods as also belonging to

315-434: A funneling effect, which channels the winds into the relatively narrow Drake Passage . Hope Bay , at 63°23′S 057°00′W  /  63.383°S 57.000°W  / -63.383; -57.000 , is near the northern extremity of the peninsula, Prime Head , at 63°13′S. Near the tip at Hope Bay is Sheppard Point . The part of the peninsula extending northeastwards from a line connecting Cape Kater to Cape Longing

420-418: A genus with overall similar morphology and proportions to Morrosaurus . In addition, there is a unique combination of two features that by themselves are not unique features. In the femur, the lesser trochanter is positioned forward and to the outside of the greater trochanter. In the tibia, medial malleolus has a triangular shape from the front and a concave surface from the same angle. Morrosaurus

525-523: A grounded ice sheet. Tierra del Fuego , the southernmost tip of South America , is about 1,000 km (620 miles) away across the Drake Passage . The Antarctic Peninsula is 522,000 square kilometres (202,000 sq mi) in area and 80% ice-covered. The marine ecosystem around the western continental shelf of the Antarctic Peninsula (WAP) has been subjected to rapid climate change . Over

630-399: A later point than did, consistent with other dinosaurs. Neonatal fossils of elasmarians from Australia, which offer strong evidence of elasmarians living year round in high-latitude conditions rather than being migratory in nature, were similarly found to display growth rates very similar to those of other ornithopods such as Orodromeus . The discovery of Morrosaurus was concurrent with

735-510: A maritime Antarctic climate, is the mildest part of the Antarctic Peninsula. Within this part of the Antarctic Peninsula, temperatures exceed 0 °C (32 °F) for 3 or 4 months during the summer, and rarely fall below −10 °C (14 °F) during the winter. Farther south along the west coast and the northeast coast of the peninsula, mean monthly temperatures exceed 0 °C (32 °F) for only one or two months of summer and average around −15 °C (5 °F) in winter. The east coast of

840-723: A marked increase in the number of research bases as Britain, Chile and Argentina competed to make claims over the same area. Meteorology and geology were the primary research subjects. Since the peninsula has the mildest climate in Antarctica, the highest concentration of research stations on the continent can be found there, or on the many nearby islands, and it is the part of Antarctica most often visited by tour vessels and yachts. Occupied bases include Base General Bernardo O'Higgins Riquelme , Bellingshausen Station , Carlini Base , Comandante Ferraz Antarctic Station , Palmer Station , Rothera Research Station , and San Martín Base . Today on

945-613: A north–south direction. James Ross Island is separated from Trinity Peninsula , at the tip of the Antarctic Peninsula to the northwest, by the Prince Gustav Channel . Vega Island is to the north of the island, separated from James Ross Island by the Herbert Sound . Erebus and Terror Gulf is to the northeast. Seymour Island and Snow Hill Island are to the southeast. It is in the James Ross Island group . The island

1050-501: A reduction in atmospheric CO 2 concentrations. Initially, during the Eocene, this climate cooling resulted in a decrease in diversity of the angiosperm-dominated vegetation that inhabited the northern Antarctic Peninsula. During the Oligocene, about 34–23  Ma , these woodlands were replaced by a mosaic of southern beech ( Nothofagus ) and conifer-dominated woodlands and tundra as

1155-438: Is 35 cm (14 in) or less with occasional rain. Along the east coast of the Antarctic Peninsula south of 63° S, precipitation ranges from 10 to 15 cm (3.9 to 5.9 in). In comparison, the subantarctic islands have precipitation of 100–200 cm (39–79 in) per year and the dry interior of Antarctica is a virtual desert with only 10 cm (3.9 in) precipitation per year. The climate in and around

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1260-549: Is a cormorant which is native to many sub-Antarctic islands, the Antarctic Peninsula and southern South America. Also present are the Antarctic petrel , Antarctic shag , king penguin , macaroni penguin , and Arctic tern . Although this very remote part of the world has never been inhabited and is protected by the Antarctic Treaty System , which bans industrial development, waste disposal and nuclear testing, there

1365-615: Is an active volcano at the southern end of this rift zone. Notable fossil locations include the Late Jurassic to Early Cretaceous Fossil Bluff Group of Alexander Island , Early Cretaceous sediments in Byers Peninsula on Livingston Island , and the sediments on Seymour Island , which include the Cretaceous extinction . The peninsula is very mountainous, its highest peaks rising to about 2,800 m (9,200 ft). Notable peaks on

1470-652: Is called the Trinity Peninsula. Brown Bluff is a rare tuya and Sheppard Nunatak is found here also. The Airy , Seller , Fleming and Prospect Glaciers form the Forster Ice Piedmont along the west coast of the peninsula. Charlotte Bay , Hughes Bay and Marguerite Bay are all on the west coast as well. On the east coast is the Athene Glacier ; the Arctowski and Åkerlundh Nunataks are both just off

1575-401: Is descriptive, this being one of the most active glaciers on the island. 64°24′S 57°41′W  /  64.400°S 57.683°W  / -64.400; -57.683 . A point formed by a rock cliff surmounted by ice, located 8 nautical miles (15 km; 9.2 mi) east-northeast of Cape Foster. First surveyed by SwedAE, 1901-04, under Otto Nordenskjold. Resurveyed by FIDS in 1948,

1680-484: Is descriptive; when viewed from seaward the feature resembles a skep type beehive. 64°05′S 57°09′W  /  64.083°S 57.150°W  / -64.083; -57.150 . A low ice-covered point on the northeast coast of James Ross Island, 5 nautical miles (9.3 km; 5.8 mi) northwest of Cape Gage. First seen and roughly surveyed by SwedAE, 1901-04, under Otto Nordenskjold. Resurveyed by FIDS in 1945. Named by UK-APC for Anton Olsen Ula, boatswain on

1785-668: Is evident in the Scotia Metamorphic Complex, which outcrops on Elephant Island , along with Clarence and Smith Islands of the South Shetland Islands . The Drake Passage opened about 30 Ma as Antarctica separated from South America. The South Shetland Island separated from Graham Land about 4 Ma as a volcanic rift formed within the Bransfield Strait . Three dormant submarine volcanoes along this rift include The Axe, Three Sisters, and Orca. Deception Island

1890-591: Is noted as more developed in elasmarian taxa than in other ornithopods such as Hypsilophodon . In 2020 a study was conducted on the growth rate of Morrosaurus , and its relative Trinisaura , through use of histological study of thin samples from the holotype fibula and fourth metatarsal . Ornithischian dinosaurs living in polar regions in the Northern Hemisphere (such as Edmontosaurus and Pachyrhinosaurus typically show different growth rates than relatives from lower latitutes, owing to

1995-464: Is similar geologically and in appearance to Terrapin Hill in the northeast portion of the island; hence the application of a related name. 64°23′S 57°22′W  /  64.383°S 57.367°W  / -64.383; -57.367 . An isolated, steep-sided, flat-topped rock mass, 400 metres (1,300 ft) high, on the southeast extremity of James Ross Island. First seen, roughly surveyed, and given

2100-666: Is still a threat to these fragile ecosystems from increasing tourism, primarily on cruises across the Southern Ocean from the port of Ushuaia , Argentina . A rich record of fossil leaves, wood, pollen, and flowers demonstrates that flowering plants thrived in subtropical climates within the volcanic island arcs that occupied the Antarctic Peninsula region during the Cretaceous and very early Paleogene periods. The analysis of fossil leaves and flowers indicates that semitropical woodlands, which were composed of ancestors of plants that live in

2205-595: The Antarctic Circle , is the most northerly part of Antarctica, it has the mildest climates within this continent. Its climate is therefore classified as a tundra , rather than an ice cap . Its temperatures are warmest in January, averaging 1 to 2 °C (34 to 36 °F), and coldest in June, averages from −15 to −20 °C (5 to −4 °F). Its west coast from the tip of the Antarctic Peninsula south to 68° S , which has

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2310-505: The Antarctic hair grass ( Deschampsia antarctica ) and Antarctic pearlwort ( Colobanthus quitensis ) are found on the northern and western parts of the Antarctic Peninsula, including offshore islands, where the climate is relatively mild. Lagotellerie Island in Marguerite Bay is an example of this habitat. Xanthoria elegans and Caloplaca are visible crustose lichens seen on coastal rocks. Antarctic krill are found in

2415-650: The Cretaceous to present times, and outcrops are found along the Gerlache Strait , the Lemaire Channel , Argentine Islands , and Adelaide Island . These rocks in western Graham Land include andesite lavas and granite from the magma , and indicate Graham Land was a continuation of the Andes . This line of volcanoes are associated with subduction of the Phoenix Plate . Metamorphism associated with this subduction

2520-645: The Gondwanaland supercontinent. Analysis of paleontologic, stratigraphic, and sedimentologic data acquired from the study of drill core and seismic acquired during the Shallow Drilling on the Antarctic Continental Shelf (SHALDRIL) and other projects and from fossil collections from and rock outcrops within Alexander, James Ross, King George, Seymour, and South Shetland Islands has yielded a record of

2625-519: The South Dakota School of Mines & Technology discovered the bones of a theropod dinosaur on the island. Nicknamed "Naze" after the northerly Naze Peninsula on which it was found, the Late Cretaceous remains include an upper jaw and teeth, and most of the lower legs and feet. Little information is available, but the shape of the leg and feet indicate it was a runner. In 2019, it was given

2730-547: The Swedish Antarctic Expedition , one of the first expeditions to explore parts of Antarctica. They landed on the Antarctic Peninsula in February 1902, aboard the ship Antarctic , which sank not far from the peninsula. All crew were rescued by an Argentine ship. The British Graham Land expedition between 1934 and 1937 carried out aerial surveys using a de Havilland Fox Moth aircraft, and concluded that Graham Land

2835-487: The United Kingdom . None of these claims have international recognition and, under the Antarctic Treaty System , the respective countries do not attempt to enforce their claims. The British claim, however, is recognised by Australia , France , New Zealand , and Norway . Argentina has the most bases and personnel stationed on the peninsula. The most likely first sighting of the Antarctic Peninsula, and therefore also of

2940-647: The United States Geological Survey . Antarctic Peninsula The Antarctic Peninsula is part of the larger peninsula of West Antarctica , protruding 1,300 km (810 miles) from a line between Cape Adams ( Weddell Sea ) and a point on the mainland south of the Eklund Islands . Beneath the ice sheet that covers it, the Antarctic Peninsula consists of a string of bedrock islands; these are separated by deep channels whose bottoms lie at depths considerably below current sea level. They are joined by

3045-628: The dinosaur genus Antarctopelta , which was the first dinosaur fossil to be found on Antarctica. Paleogene and Early Eocene marine sediments that outcrop on Seymour Island contain plant-rich horizons. The fossil plants are dominated by permineralized branches of conifers and compressions of angiosperm leaves, and are found within carbonate concretions. These Seymour Island region fossils date to about 51.5–49.5  Ma and are dominated by leaves, cone scales, and leafy branches of Araucarian conifers, very similar in all respects to living Araucaria araucana (monkey puzzle) from Chile. They suggest that

3150-408: The killer whale . The animals of Antarctica live on food they find in the sea—not on land—and include seabirds , seals and penguins . The seals include: leopard seal ( Hydrurga leptonyx ), Weddell seal ( Leptonychotes weddellii ), the huge southern elephant seal ( Mirounga leonina ), and crabeater seal ( Lobodon carcinophagus ). Penguin species found on the peninsula, especially near

3255-440: The paleontology , sedimentology , stratigraphy , structural geology , and volcanology of glacial and nonglacial deposits of the Antarctic Peninsula has allowed the reconstruction of the paleoclimatology and prehistoric ice sheet fluctuation of it for over the last 100 million years. This research shows the dramatic changes in climate, which have occurred within this region after it reached its approximate position within

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3360-493: The tibia , the underside of the tibia, the upper half of the foot, the bottom of the midfoot and the top of the first joint of the third toe. The only known specimen, thought to represent an adult, is estimated to have belong to an individual 4.5–5 metres (15–16 ft) in length. This makes it larger and more robust in skeletal build than many of its relatives, including the fellow Antarctic genus Trinisaura , only 1.5 metres (4.9 ft) in length. The fragmentary nature of

3465-773: The Antarctic Circle during the Cretaceous Period. The Fossil Bluff Group , which outcrops within Alexander Island , provides a detailed record, which includes paleosols and fossil plants, of Middle Cretaceous ( Albian ) terrestrial climates. The sediments that form the Fossil Bluff Group accumulated within a volcanic island arc , which now forms the bedrock backbone of the Antarctic Peninsula, in prehistoric floodplains and deltas and offshore as submarine fans and other marine sediments. As reflected in

3570-525: The Antarctic Peninsula formed as the bedrock islands underlying it were overridden and joined by an ice sheet in the early Pliocene about 5.3–3.6  Ma . During the Quaternary period, the size of the West Antarctic Ice Sheet has fluctuated in response to glacial–interglacial cycles. During glacial epochs, this ice sheet was significantly thicker than it is currently and extended to the edge of

3675-404: The Antarctic Peninsula is changing dramatically in 2024. The most recent temperature recorded was 10°C, which is higher than the peninsula region's average and deviates from the patterns of typical temperatures. The peninsula is getting very much affected by these sudden climate changes. In past years, researchers have seen northwesterly winds over the peninsula, and it is proven that this is one of

3780-673: The Antarctic Peninsula northward of a line between Cape Jeremy and Cape Agassiz ; and Palmer Land the part southward of that line, which is roughly 69° S. Palmer Land is named for the United States seal hunter Nathaniel Palmer . The Chilean name for the feature, O'Higgins Land, is in honor of Bernardo O'Higgins , the Chilean patriot and Antarctic visionary. Most other Spanish-speaking countries call it la Península Antártica , though Argentina also officially refers to this as Tierra de San Martín ; as of 2018 Argentina has more bases and personnel in

3885-448: The Antarctic Peninsula south of 63° S is generally much colder, with mean temperatures exceeding 0 °C (32 °F) for at most one month of summer, and winter mean temperatures ranging from −5 to −25 °C (23 to −13 °F). The colder temperatures of the southeast, Weddell Sea side, of the Antarctic Peninsula are reflected in the persistence of ice shelves that cling to the eastern side. Precipitation varies greatly within

3990-531: The Antarctic Peninsula there are many abandoned scientific and military bases. Argentina's Esperanza Base was the birthplace of Emilio Marcos Palma , the first person to be born in Antarctica. The grounding of the Argentine ship the ARA Bahía Paraíso and subsequent 170,000 US gal (640,000 L; 140,000 imp gal) oil spill occurred near the Antarctic Peninsula in 1989. Antarctica

4095-504: The Antarctic Peninsula was overridden by an ice sheet, which has persisted without any interruption to this day, in the early Pliocene, about 5.3–3.6  Ma . Morrosaurus Morrosaurus is an extinct genus of herbivorous elasmarian dinosaur that lived in the late Cretaceous in Antarctica . The only known species is the type Morrosaurus antarcticus . In 2002, the Argentine paleontologist Fernando Novas reported

4200-423: The Antarctic Peninsula. From the tip of the Antarctic Peninsula to 68° S, precipitation averages 35–50 cm (14–20 in) per year. A good portion of this precipitation falls as rain during the summer, on two-thirds of the days of the year, and with little seasonal variation in amounts. Between about 68° S and 63° S on the west coast of the Antarctic Peninsula and along its northeast coast, precipitation

4305-643: The Antarctic the ship of the above Swedish expedition. 69°09′S 57°14′W  /  69.150°S 57.233°W  / -69.150; -57.233 . A glacier, 5 nautical miles (9.3 km; 5.8 mi) long, on the east side of James Ross Island. It flows into Erebus and Terror Gulf just north of Cape Gage. Surveyed by FIDS in 1945 and 1953. Named by UK-APC for John A. Coley of FIDS, meteorological assistant at Hope Bay in 1952 and 1953. 64°10′S 57°05′W  /  64.167°S 57.083°W  / -64.167; -57.083 . A rocky promontory forming

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4410-515: The Cretaceous thermal maximum the climate, both regionally and globally, appears to have cooled as seen in the Antarctic fossil wood record. Later, warm high-latitude climates returned to the Antarctic Peninsula region during the Paleocene and early Eocene as reflected in fossil plants. Abundant plant and marine fossils from Paleogene marine sediments that outcrop on Seymour Island indicate the presence of cool and moist, high-latitudes environment during

4515-581: The Late Cretaceous ( Coniacian and Santonian -early Campanian ) strata of the Hidden Lake and Santa Maria formations, which outcrop within James Ross , Seymour , and adjacent islands, indicate that this emergent volcanic island arc enjoyed warm temperate or subtropical climates with adequate moisture for growth and without extended periods of below freezing winter temperatures. After the peak warmth of

4620-720: The UK-APC in 1987 after Reinhard Förster (1935-87), West German geologist from the University of Munich, who was a member of the British Antarctic Survey (BAS) field party to the area, 1985-86. 64°03′S 57°18′W  /  64.050°S 57.300°W  / -64.050; -57.300 . A high ice-free point 5 nautical miles (9.3 km; 5.8 mi) west-northwest of Ula Point on the northeast coast of James Ross Island. Surveyed by Falkland Islands Dependencies Survey (FIDS) first in 1945, then again in 1953. The UK-APC name

4725-506: The adjacent parts of the prehistoric Antarctic Peninsula were covered by forests that grew in a cool and moist, high-latitude environment during the early Eocene. During the Cenozoic climatic cooling, the Antarctic Peninsula was the last region of Antarctica to have been fully glaciated according to current research. As a result, this region was probably the last refugium for plants and animals that had inhabited Antarctica after it separated from

4830-437: The changes in terrestrial vegetation that occurred within the Antarctic Peninsula over the course of the past 37 million years. This research found that vegetation within the Antarctic Peninsula changed in response to a progressive climatic cooling that started with the initiation of mountain glaciation in the latest Eocene, about 37–34  Ma . The cooling was contemporaneous with glaciation elsewhere in Antarctica and

4935-644: The characteristic color of the exposed rock cliffs. 64°22′30″S 57°46′13″W  /  64.375°S 57.7702778°W  / -64.375; -57.7702778 A bay entered west of Jefford Point on the south side of James Ross Island. Named by UK Antarctic Place-names Committee (UK-APC) (2006) in association with Swift Glacier which flows southward into the bay. 64°22′S 57°46′W  /  64.367°S 57.767°W  / -64.367; -57.767 . A steep glacier about 2 nautical miles (3.7 km; 2.3 mi) long, close west of Jefford Point. Named by UK-APC following FIDS surveys, 1958-61. The name

5040-407: The climate continued to cool. By middle Miocene, 16–11.6  Ma , a tundra landscape completely replaced any remaining woodlands. At this time, woodlands became completely extirpated from the Antarctic Peninsula and all of Antarctica. A tundra landscape probably persisted until about 12.8  Ma when the transition from a temperate, alpine glaciation to a dynamic ice sheet occurred. Eventually,

5145-409: The climate optimum, a distinct climate cooling, which lasted until historic times, occurred. The Antarctic Peninsula is a part of the world that is experiencing extraordinary warming. Each decade for the last five, average temperatures in the Antarctic Peninsula have risen by 0.5 °C (0.90 °F). Ice mass loss on the peninsula occurred at a rate of 60 billion tons / year in 2006, with

5250-466: The cold, southern environments they lived in, elasmarians were able to succeed in such ecosystems due to the existing possession of necessary adaptations to thrive there. Higher growth rate was noted in Morrosaurus as compared to Trinisaura , consistent with being a larger species. Additionally, it was found the animals reached their sexual maturity well before their skeletal maturity, and ceased growth at

5355-600: The continental shelves. During interglacial epochs, the West Antarctica Ice Sheet was thinner than during glacial epochs and its margins lay significantly inland of the continental margins. During the Last Glacial Maximum , about 20,000 to 18,000 years ago, the ice sheet covering the Antarctic Peninsula was significantly thicker than it is now. Except for a few isolated nunataks , the Antarctic Peninsula and its associated islands were completely buried by

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5460-760: The descriptive name "The Watch Tower" by Otto Nordenskjold of the SwedAE in March 1902. 64°23′00″S 57°23′00″W  /  64.3833333°S 57.3833333°W  / -64.3833333; -57.3833333 . A small glacier flowing south-southeast to Admiralty Sound along the west side of The Watchtower. Named by UK-APC in 1995 after Michael Kingsley Howarth (b. 1932), Deputy Keeper of Paleontology, British Museum (Natural History), 1980-92, and author of Falklands Islands Dependencies Survey (FIDS) Scientific Report No. 21, Alexander Island. [REDACTED]  This article incorporates public domain material from websites or documents of

5565-425: The discovery of a partial skeleton of a euornithopod in Antarctica. In 2016 these remains were the basis for naming the type species Morrosaurus antarcticus , named and described by Sebastian Rozadilla, Federico Lisandro Agnolin, Fernando Emilio Novas, Alexis Rolando Aranciaga Mauro, Matthew J. Motta, Juan Manuel Lirio Marcelo, and Pablo Isasi. The genus name refers to the site of El Morro on James Ross Island , where

5670-468: The early Eocene. Detailed studies of the paleontology, sedimentology, and stratigraphy of glacial and nonglacial deposits within the Antarctic Peninsula and adjacent parts of the Weddell Sea and its Pacific continental shelf have found that it has become progressively glaciated as the climate of Antarctica dramatically and progressively cooled during the last 37 million years. This progressive cooling

5775-524: The east extremity of James Ross Island and the west side of the north entrance to Admiralty Sound . Discovered by a British expedition 1839-43, under James Clark Ross , who named it for V. Admiral William Hall Gage , a Lord Commissioner of the Admiralty. From west to east 64°23′S 58°13′W  /  64.383°S 58.217°W  / -64.383; -58.217 . A rocky point 4 nautical miles (7.4 km; 4.6 mi) southeast of Cape Broms, on

5880-496: The east coast. A number of smaller peninsulas extend from the main Antarctic Peninsula, including Hollick-Kenyon Peninsula and Prehn Peninsula at the base of the Antarctic Peninsula. Also located here are the Scaife Mountains . The Eternity Range is found in the middle of the peninsula. Other geographical features include Avery Plateau , the twin towers of Una Peaks . Because the Antarctic Peninsula, which reaches north of

5985-554: The emergent parts of the volcanic island arc, the eroded roots of which now form the central part of the Antarctic Peninsula, were covered by either warm temperate or subtropical forests. These fossil plants are indicative of tropical and subtropical forest at high paleolatitudes during the Middle and Late Cretaceous, which grew in climates without extended periods of below freezing winter temperatures and with adequate moisture for growth. The Cretaceous strata of James Ross Island also yielded

6090-625: The extreme temperatures of their environments, but studies have failed to find the same signs in Antarctic animals. The study confirmed this pattern in elasmarians, with comparison with South American elasmarian Gasparinisaura finding incredibly similar histology to the Antarctic genera. All three show rapid growth with periodic interruptions, variation in growth marks, and changes in growth rate across their life cycle, growing slower as they aged. Similar growth strategies are reported in other ornithopods from much lower latitudes. This indicates that rather than adapting their growth physiology in response to

6195-503: The femur forms an S-shape, with the back edge thick across and the front edge thin, similar to the condition seen in other elasmarians Anabisetia , Notohypsilophodon , and Gasparinisaura but displayed to a more extreme extent. The fourth metatarsal bone has a prominent rearward projection that wraps around the third metatarsal, likewise similar but more developed to the condition seen in Gasparinisaura as well as Kangnasaurus ,

6300-429: The first evidence of a previously hypothesized uniting clade of ornithopod dinosaurs from the continents that had comprised Gondwana . The distinction between fauna of this part of the world as compared with the northern hemisphere equivalent Laurasia had long been noted, but evidence was traditionally lacking for a biogeographic link for dinosaurs between the different Gondwanan regions. Brazil and Northern Africa shared

6405-452: The genus. The femur seems to have been rather gracile, though more stout than in Trinisaura , as was the elongate foot, with the central third metatarsal being larger than the others. A series of distinctive features characterizes the genus. Two of these are autapomorphies , completely unique traits acquired by the taxon. In bottom view, the greater trochanter near the top of

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6510-410: The greatest change occurring in the northern tip of the peninsula. Seven ice shelves along the Antarctic Peninsula have retreated or disintegrated in the last two decades. Research by the United States Geological Survey has revealed that every ice front on the southern half of the peninsula experienced a retreat between 1947 and 2009. According to a study by the British Antarctic Survey , glaciers on

6615-469: The group, as well as possibly Kangnasaurus from Africa. Similar biogeographic patterns have been observed in megaraptoran theropods, diamantinasaurian sauropods, and parankylosaurian ankylosaurs. These discoveries of connected endemic Gondwanan ecosystems have overturned the traditional view of the southern continents, including the fauna seen in Late Cretaceous Antarctic, acting as

6720-562: The hindlimb anatomy of Morrosaurus and other elasmarians, notably the slim metatarsus , it's thought they were very capable runners, distinguishing them from other herbivorous dinosaurs they lived alongside. Elements of relatives not preserved in Morrosaurus such as expanded chevrons and distinctive bony intercostal plates along the torso would've further aided their cursorial abilities by improving tail balance and musculature control as well as breathing efficiency. This developed tail musculature and running ability of elasmarians

6825-489: The ice sheet from the Pacific outer continental shelf and the continental margin within the Weddell Sea. Within the Weddell Sea, the transition from grounded ice to a floating ice shelf occurred about 10,000 years ago. The deglaciation of some locations within the Antarctic Peninsula continued until 4,000 to 3,000 years ago. Within the Antarctic Peninsula, an interglacial climatic optimum occurred about 3,000 to 5,000 years ago. After

6930-468: The ice sheet is melting nonstop. Because of issues concerning global climate change, the Antarctic Peninsula and adjacent parts of the Weddell Sea and its Pacific continental shelf have been the subject of intensive geologic, paleontologic, and paleoclimatic research by interdisciplinary and multinational groups over the last several decades. The combined study of the glaciology of its ice sheet and

7035-438: The ice sheet. In addition, the ice sheet extended past the present shoreline onto the Pacific outer continental shelf and completely filled the Weddell Sea up to the continental margin with grounded ice. The deglaciation of the Antarctic Peninsula largely occurred between 18,000 and 6,000 years ago as an interglacial climate was established in the region. It initially started about 18,000 to 14,000 years ago with retreat of

7140-583: The land by pack ice . Separating the peninsula from nearby islands are the Antarctic Sound , Erebus and Terror Gulf , George VI Sound , Gerlache Strait and the Lemaire Channel . The Lemaire Channel is a popular destination for tourist cruise ships that visit Antarctica. Further to the west lies the Bellingshausen Sea and in the north is the Scotia Sea . The Antarctic Peninsula and Cape Horn create

7245-803: The leader of a British expedition to this area in 1842 that discovered and roughly charted a number of points along the eastern side of the island. The style, "James" Ross Island is used to avoid confusion with the more widely known Ross Island in McMurdo Sound . Two dinosaur-bearing formations are present on the island, both from the Upper Cretaceous : the Santa Marta Formation and the Snow Hill Island Formation . These are two of only three known formations to have dinosaur fossils in Antarctica. The first dinosaur discovered in Antarctica

7350-428: The material precludes saying much about the preserved regions. It is united anatomically with other elasmarians by the strongly compressed outer front edge of the greater trochanter , lacking the distinct cleft and thick edge seen in other types of ornithopod. Other uniting traits of elasmarians seen in the humerus and vertebrae cannot be evaluated in Morrosaurus due to their lack of preservation in

7455-596: The most common on the Antarctic Peninsula are the chinstrap and gentoo, with the only breeding colony of emperor penguins in West Antarctica an isolated population on the Dion Islands , in Marguerite Bay on the west coast of the peninsula. Most emperor penguins breed in East Antarctica. Seabirds of the Southern Ocean and West Antarctica found on the peninsula include: southern fulmar ( Fulmarus glacialoides ),

7560-487: The name Imperobator antarcticus . It was large, about the size of Utahraptor . It is the second Antarctic theropod discovered, after Cryolophosaurus . An ornithopod was found in the Snow Hill Island Formation by Argentine paleontologists Rodolfo Aníbal Coria and Juan José Moly in 2008. In 2013, Coria named it Trinisaura santamartaensis . In 2015, an iguanodontid found in 2002 by Fernando Novas

7665-628: The narrow foot with a thin fourth metatarsal which indicates a high speed running; subsequently expanded chevrons , a feature that is associated with a greater surface area for attachment of the lateral muscles of the tail, which would give good control of the movements of this; and a curved humerus which demonstrates the absence of a deltopectoral ridge and therefore that the front leg was not used for walking. It cannot be determined, however, if Morrosaurus itself possessed these characteristics due to their limited remains. The existence of this clade may indicate that Patagonia, Antarctica and Australia shared

7770-482: The past 50 years, the warm, moist maritime climate of the northern WAP has shifted south. This climatic change increasingly displaces the once dominant cold, dry continental Antarctic climate. This regional warming has caused multi-level responses in the marine ecosystem such as increased heat transport , decreased sea ice extent and duration, local declines in ice-dependent Adélie penguins , increase in ice-tolerant gentoo and chinstrap penguins, accelerated greening due to

7875-486: The peninsula are not only retreating but also increasing their flow rate as a result of increased buoyancy in the lower parts of the glaciers. Professor David Vaughan has described the disintegration of the Wilkins Ice Shelf as the latest evidence of rapid warming in the area. The Intergovernmental Panel on Climate Change has been unable to determine the greatest potential effect on sea level rise that glaciers in

7980-402: The peninsula include Deschanel Peak , Mounts Castro , Coman , Gilbert , Jackson , William , Owen , Scott , and Hope , which is the highest point at 3,239 m (10,627 ft), Mount William , Mount Owen and Mount Scott . These mountains are considered to be a continuation of the Andes of South America , with a submarine spine or ridge connecting the two. This is the basis for

8085-539: The peninsula is typical Antarctic tundra . The peninsula has a sharp elevation gradient, with glaciers flowing into the Larsen Ice Shelf , which experienced significant breakup in 2002. Other ice shelves on the peninsula include the George VI , Wilkins , Wordie and Bach Ice Shelves . The Filchner-Ronne Ice Shelf lies to the east of the peninsula. Islands along the peninsula are mostly ice-covered and connected to

8190-462: The peninsula than any other nation. Other portions of the peninsula are named by and after the various expeditions that discovered them, including the Bowman , Black , Danco , Davis , English , Fallières , Nordenskjöld , Loubet , and Wilkins Coasts . The first Antarctic research stations were established during World War II by a British military operation, Operation Tabarin . The 1950s saw

8295-401: The plant fossils, paleosols, and climate models, the climate was warm, humid, and seasonally dry. According to climate models, the summers were dry and winters were wet. The rivers were perennial and subject to intermittent flooding as the result of heavy rainfall. Warm high-latitude climates reached a peak during the mid-Late Cretaceous Cretaceous Thermal Maximum . Plant fossils found within

8400-472: The position advanced by Chile and Argentina for their territorial claims. The Scotia Arc is the island arc system that links the mountains of the Antarctic Peninsula to those of Tierra del Fuego . There are various volcanoes in the islands around the Antarctic Peninsula. This volcanism is related to extensional tectonics in Bransfield Rift to the west and Larsen Rift to the east. The landscape of

8505-456: The reasons for the peninsula constantly melting and snow sublimation in 2024. Researchers are observing similar situations in 2024. Melting events have been observed on the eastern and western sides of the Peninsula in February and March. All three are contributing to the melting of ice in several Antarctic Peninsula areas, such as Larsen C and B. Furthermore, data from NASA's research indicates that

8610-618: The records being lost in a fire at Hope Bay, it was surveyed again by FIDS in 1952. Named by UK-APC for Brian Jefford, FIDS surveyor at Hope Bay in 1948, and at Admiralty Bay in 1949. 64°22′00″S 57°35′00″W  /  64.3666667°S 57.5833333°W  / -64.3666667; -57.5833333 . A ridge, 3 kilometres (1.9 mi) long, trending north-northwest – south-southeast, midway between Jefford Point and Tortoise Hill, southeast James Ross Island. Named by UK Antarctic Place-names Committee (UK-APC) in 1995 after Simon Andrew Lomas (b. 1965), British Antarctic Survey (BAS) geologist who

8715-516: The region may cause. The coasts of the peninsula have the mildest climate in Antarctica and moss and lichen -covered rocks are free of snow during the summer months, although the weather is still intensely cold and the growing season very short. The plant life today is mainly mosses, lichens and algae adapted to this harsh environment, with lichens preferring the wetter areas of the rocky landscape. The most common lichens are Usnea and Bryoria species. Antarctica's two flowering plant species,

8820-509: The remains of the species were found. The specific name refers to Antarctica. The holotype specimen MACN Pv 197 , was found in a layer of the Snow Hill Island Formation (Cape Lambe, previously assigned to the Lopez de Bertodano Formation ), dating to the Maastrichtian age. The remains consists in a right hind leg, including the top of the femur , the lower end of the femur, the upper part of

8925-546: The same type of fauna. The exact phylogenetic relationships within this clade could not be identified, except for Gasparinisaura , which proved to be the most basal member of group. Cladogram based in the phylogenetic analysis of Rozadilla et al ., 2016: Hypsilophodon Thescelosaurus Gasparinisaura Morrosaurus Trinisaura Macrogryphosaurus Notohypsilophodon Talenkauen Anabisetia Parksosaurus Kangnasaurus Rhabdodontidae Tenontosaurus Dryomorpha Based on

9030-465: The scavenging southern giant petrel ( Macronectes giganteus ), Cape petrel ( Daption capense ), snow petrel ( Pagodroma nivea ), the small Wilson's storm-petrel ( Oceanites oceanicus ), imperial shag ( Phalacrocorax atriceps ), snowy sheathbill ( Chionis alba ), the large south polar skua ( Catharacta maccormicki ), brown skua ( Catharacta lönnbergi ), kelp gull ( Larus dominicanus ), and Antarctic tern ( Sterna vittata ). The imperial shag

9135-432: The seas surrounding the peninsula and the rest of the continent. The crabeater seal spends most of its life in the same waters feeding on krill. Bald notothen is a cryopelagic fish that lives in sub-zero water temperatures around the peninsula. Vocalizations of the sei whale can be heard emanating from the waters surrounding the Antarctic Peninsula. Whales include the Antarctic minke whale , dwarf minke whale , and

9240-734: The south side of James Ross Island. Discovered by a British expedition 1839-43, under James Clark Ross , who named it for Captain Henry Foster, RN, leader of a British expedition in the Chanticleer , 1828-31. The cape was mapped by the SwedAE under Nordenskjold, 1901-04. 64°23′S 57°52′W  /  64.383°S 57.867°W  / -64.383; -57.867 . A prominent round hill 860 metres (2,820 ft) high with distinctive convex slopes, 2 nautical miles (3.7 km; 2.3 mi) inland between Cape Foster and Jefford Point. Named by UK-APC following FIDS surveys, 1958-61. The name records

9345-450: The southwest coast of James Ross Island, flowing southwest into Carlsson Bay. Probably first seen by Doctor Otto Nordenskjold in 1903. Surveyed by FIDS in 1945. Named by UK-APC for Murdo F. Tait, FIDS meteorological observer at Hope Bay in 1952 and 1953. 64°27′S 57°59′W  /  64.450°S 57.983°W  / -64.450; -57.983 . A cape lying 2 nautical miles (3.7 km; 2.3 mi) southeast of Carlsson Bay on

9450-641: The southwest side of James Ross Island. First seen and surveyed in 1903 by the SwedAE under Nordenskjold, who named it Cape Nygren after G. Nygren, Swedish chemist who contributed toward the cost of the expedition. It was resurveyed by the FIDS in 1952. Point is considered a more suitable descriptive term for this feature than cape. 64°24′S 58°04′W  /  64.400°S 58.067°W  / -64.400; -58.067 . A square bay, 2.5 nautical miles (4.6 km; 2.9 mi) in extent, entered 3 nautical miles (5.6 km; 3.5 mi) northwest of Cape Foster on

9555-418: The southwest side of James Ross Island. First seen and surveyed in 1903 by the SwedAE under Nordenskjold, who named it for J. Carlsson of Sweden who contributed toward the cost of the expedition. The bay was resurveyed by the FIDS in 1952-53. 64°22′S 58°02′W  /  64.367°S 58.033°W  / -64.367; -58.033 . A glacier about 4 nautical miles (7.4 km; 4.6 mi) long on

9660-399: The spread of moss, alterations in phytoplankton and zooplankton community composition as well as changes in krill recruitment, abundance and availability to predators. The Antarctic Peninsula is currently dotted with numerous research stations, and nations have made multiple claims of sovereignty . The peninsula is part of disputed and overlapping claims by Argentina , Chile , and

9765-461: The tip and surrounding islands, include the chinstrap penguin , emperor penguin , gentoo penguin and the Adélie penguin . Petermann Island is the world's southernmost colony of gentoo penguins. The exposed rocks on the island is one of many locations on the peninsula that provides a good habitat for rookeries . The penguins return each year and may reach populations of more than ten thousand. Of these

9870-932: The tropics today, thrived within this region during a global thermal maximum with summer temperatures that averaged 20 °C (68 °F). The oldest fossil plants come from the middle Cretaceous (Albian) Fossil Bluff Group, which outcrop along the edge of Alexander Island. These fossils reveal that at this time the forests consisted of large conifers , with mosses and ferns in the undergrowth. The paleosols, in which trees are rooted, have physical characteristics indicative of modern soils that form under seasonally dry climates with periodic high rainfall. Younger Cretaceous strata, which outcrop within James Ross, Seymour, and adjacent islands, contain fossil plants of Late Cretaceous angiosperms with leaf morphotypes that are similar to those of living families such as Sterculiaceae, Lauraceae, Winteraceae, Cunoniaceae, and Myrtaceae. They indicate that

9975-867: The west, include: From west to east 64°07′S 57°49′W  /  64.117°S 57.817°W  / -64.117; -57.817 . A rock crag rising to 905 metres (2,969 ft) high northwest of Mount Haddington . It provides the highest exposure of volcanic rock on the island. Named by the UK Antarctic Place-Names Committee (UK-APC) in 1987 after William R. Flett, geologist on Operation Tabarin at Deception Island (Base Leader), 1943-44, and Hope Bay, 1944–45. 64°01′S 57°33′W  /  64.017°S 57.550°W  / -64.017; -57.550 . Cliffs located east-northeast of Stark Point, running east–west for 2 nautical miles (3.7 km; 2.3 mi) and rising to 550 metres (1,800 ft) high in northern James Ross Island. Named by

10080-494: The whole Antarctic mainland, was on 27 January 1820 by an expedition of the Imperial Russian Navy led by Fabian Gottlieb von Bellingshausen . But the party did not recognize as the mainland what they thought was an icefield covered by small hillocks. Three days later, on 30 January 1820, Edward Bransfield and William Smith , with a British expedition, were the first to chart part of the Antarctic Peninsula. This area

10185-668: Was Antarctopelta oliveroi , a medium-sized ankylosaur found on James Ross Island by Argentinian geologists Eduardo Olivero and Roberto Scasso in 1986. The dinosaur was recovered from the Campanian stage of the Upper Cretaceous Santa Marta Formation , about 2 km (1.2 mi) south of Santa Marta Cove on the north part of the island. The ankylosaur was not formally named until 2006. In December 2003, U.S. paleontologist Judd Case from Saint Mary's College of California and U.S. geologist James Martin from

10290-483: Was a member of the British Antarctic Survey (BAS) field party in the area, 1994-95. 64°22′S 57°30′W  /  64.367°S 57.500°W  / -64.367; -57.500 . A hill more than 500 metres (1,600 ft) high, 3 nautical miles (5.6 km; 3.5 mi) west of The Watchtower at the southeast corner of James Ross Island. Named by UK-APC following FIDS surveys, 1958-61. The feature

10395-429: Was classified in the group Iguanodontia , as a basal member of Euiguanodontia. This in turn formed a clade with other ornithopods of Patagonia and Antarctica, particularly Trinisaura , Gasparinisaura , Anabisetia , Notohypsilophodon , Talenkauen and Macrogryphosaurus in a group called Elasmaria , whose members are distinguished by their adaptation to a running lifestyle which would be reflected by

10500-522: Was connected to the Antarctic mainland by an ice shelf until 1995, when the ice shelf collapsed, making the Prince Gustav Channel passable for the first time. Mendel Polar Station , the first Czech Antarctic Base, is located on the island. James Ross Island was charted in October 1903 by the Swedish Antarctic Expedition (SwedAE) under Otto Nordenskiöld , who named it for Sir James Clark Ross ,

10605-442: Was contemporaneous with a reduction in atmospheric CO 2 concentrations. During this climatic cooling, the Antarctic Peninsula was probably the last region of Antarctica to have been fully glaciated . Within the Antarctic Peninsula, mountain glaciation was initiated during the latest Eocene, about 37–34  Ma . The transition from temperate, alpine glaciation to a dynamic ice sheet occurred about 12.8  Ma . At this time,

10710-594: Was later to be called Trinity Peninsula and is the extreme northeast portion of the peninsula. The next confirmed sighting was in 1832 by John Biscoe , a British explorer, who named the northern part of the Antarctic Peninsula as Graham Land . The first European to land on the continent is also disputed. A 19th-century seal hunter , John Davis , was almost certainly the first. But, sealers were secretive about their movements and their logbooks were deliberately unreliable, to protect any new sealing grounds from competition. Between 1901 and 1904, Otto Nordenskjöld led

10815-421: Was named Morrosaurus antarcticus by Sebastian Rozadilla, Federico Lisandro Agnolin, Fernando Emilio Novas, Alexis Rolando Aranciaga Mauro, Matthew J. Motta, Juan Manuel Lirio Marcelo and Pablo Isasi. The genus name refers to the site of El Morro on James Ross Island, where the remains of the species were found. The specific name refers to Antarctica. Download coordinates as: Notable features, clockwise from

10920-513: Was not an archipelago but a peninsula. Agreement on the name "Antarctic Peninsula" by the Advisory Committee on Antarctic Names and UK Antarctic Place-Names Committee in 1964 resolved a long-standing difference over the use of the United States' name "Palmer Peninsula" or the British name "Graham Land" for this geographic feature. This dispute was resolved by making Graham Land the part of

11025-786: Was once part of the Gondwana supercontinent . Outcrops from this time include Ordovician and Devonian granites and gneiss found in the Scar Inlet and Joerg Peninsula , while the Carboniferous - Triassic Trinity Peninsula Group are sedimentary rocks that outcrop in Hope Bay and Prince Gustav Channel . Ring of Fire volcanic rocks erupted in the Jurassic , with the breakup of Gondwana, and outcrop in eastern Graham Land as volcanic ash deposits. Volcanism along western Graham Land dates from

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