hce_kmu
104年
英文
第 52 題
📖 題組：
More than 3 million years ago, when “Lucy” was roaming the savannah of present-day Ethiopia, she may have encountered other two-legged apes not unlike her own species, Australopithecus afarensis—yet still just a wee bit strange. Represented by jawbones from three individuals, a newly described species named Australopithecus deyrimeda adds to the scatter of evidence that not one, but a range of hominin species populated the East African landscape before 3 million years ago. This could imply they were able to carve out separate niches in a stable environment based on differences in diet, foraging strategies and other behaviors. “We don't know enough yet to say anything about the nature of interaction or ecological differences between A. afarensis and A. deyiremeda,” says Stephanie Melillo of the Max Planck Institute for Evolutionary Anthropology. “We have to first know how to tell the two species apart from their fossil remains, and that is what this paper was all about.” Reported Wednesday in Nature, the new specimens—a partial upper jaw, two lower jaws, and some other fragments—were found at Burtele, in the Afar Triangle of Ethiopia, just a day’s walk from Hadar, where Lucy was found in 1974. Sediments surrounding the bones were dated to 3.3 and 3.5 million years ago, a time when A. afarensis is well known to have inhabited the region. While the new jaws share some characteristics with Lucy’s species, they differ in other respects. Some of the teeth have different root structures, and in general are smaller than A. afarensis teeth, a trait that could indicate a shift in diet. “Smaller teeth are often associated with a more meaty diet,” says Fred Spoor of University College London and the Max Planck Institute for Evolutionary Anthropology. “And the chewing muscles have migrated forward, which suggests a redistribution of chewing forces of some sort.” The species name, A. deyrimeda, derives from the local words for “close” (deyi) and “relative” (remeda)—signaling the species close relationship with other hominins. But the similarities only go so far. “We are convinced that it is different from A. afarensis. All of the evidence—published and unpublished—that we have from the localities at Burtele support our conclusion,” says study author Yohannes Haile-Selassie of the Cleveland Museum of Natural History. He notes that folding the new specimens into A. afarensis would introduce an extremely unusual amount of physical variation into the existing species. Still, “the distinctions are very, very subtle,” says paleoanthropologist Bill Kimbel of the Institute of Human Origins. “I think the authors have done a very nice job in analyzing the material, but I think it’s a judgment call as to whether you think the differences amount to a species-level difference.” A. afarensis remains by far the most conspicuous hominin in the fossil record of East Africa 3 to 4 million years ago, during a period known as the Middle Pliocene. But in the last two decades, scientists have named several others, including Australopithecus bahrelghazali from Chad, and Kenyanthropus platyops from Kenya. A. deyrimeda further swells the crowd. “There is now incontrovertible evidence to show that multiple hominins existed contemporaneously in eastern Africa during the Middle Pliocene,” the authors write. Of special interest are some enigmatic foot bones of a hominin recovered in 2009 very close to where A. deyiremeda was unearthed. The bones suggest a creature with a flexible foot and big toe capable of grasping objects, similar to a more primitive hominin called Ardipithecus ramidus, dated to 4.4 million years ago. But perplexingly, the foot bones at Burtele date back to just 3.4 million years ago: the same time period as A. deyiremeda. It’s a combination of proximity in both space and time that cannot be ignored, Kimbel says. “Figuring out whether or not that very primitive foot is the same critter as the clear australopithecine teeth and jaws that are being described now is of utmost importance,” Kimbel says. “It would mean that you could have australopithecus-like heads with more diverse options for locomotion – which is not a picture we have painted so far.”
More than 3 million years ago, when “Lucy” was roaming the savannah of present-day Ethiopia, she may have encountered other two-legged apes not unlike her own species, Australopithecus afarensis—yet still just a wee bit strange. Represented by jawbones from three individuals, a newly described species named Australopithecus deyrimeda adds to the scatter of evidence that not one, but a range of hominin species populated the East African landscape before 3 million years ago. This could imply they were able to carve out separate niches in a stable environment based on differences in diet, foraging strategies and other behaviors. “We don't know enough yet to say anything about the nature of interaction or ecological differences between A. afarensis and A. deyiremeda,” says Stephanie Melillo of the Max Planck Institute for Evolutionary Anthropology. “We have to first know how to tell the two species apart from their fossil remains, and that is what this paper was all about.” Reported Wednesday in Nature, the new specimens—a partial upper jaw, two lower jaws, and some other fragments—were found at Burtele, in the Afar Triangle of Ethiopia, just a day’s walk from Hadar, where Lucy was found in 1974. Sediments surrounding the bones were dated to 3.3 and 3.5 million years ago, a time when A. afarensis is well known to have inhabited the region. While the new jaws share some characteristics with Lucy’s species, they differ in other respects. Some of the teeth have different root structures, and in general are smaller than A. afarensis teeth, a trait that could indicate a shift in diet. “Smaller teeth are often associated with a more meaty diet,” says Fred Spoor of University College London and the Max Planck Institute for Evolutionary Anthropology. “And the chewing muscles have migrated forward, which suggests a redistribution of chewing forces of some sort.” The species name, A. deyrimeda, derives from the local words for “close” (deyi) and “relative” (remeda)—signaling the species close relationship with other hominins. But the similarities only go so far. “We are convinced that it is different from A. afarensis. All of the evidence—published and unpublished—that we have from the localities at Burtele support our conclusion,” says study author Yohannes Haile-Selassie of the Cleveland Museum of Natural History. He notes that folding the new specimens into A. afarensis would introduce an extremely unusual amount of physical variation into the existing species. Still, “the distinctions are very, very subtle,” says paleoanthropologist Bill Kimbel of the Institute of Human Origins. “I think the authors have done a very nice job in analyzing the material, but I think it’s a judgment call as to whether you think the differences amount to a species-level difference.” A. afarensis remains by far the most conspicuous hominin in the fossil record of East Africa 3 to 4 million years ago, during a period known as the Middle Pliocene. But in the last two decades, scientists have named several others, including Australopithecus bahrelghazali from Chad, and Kenyanthropus platyops from Kenya. A. deyrimeda further swells the crowd. “There is now incontrovertible evidence to show that multiple hominins existed contemporaneously in eastern Africa during the Middle Pliocene,” the authors write. Of special interest are some enigmatic foot bones of a hominin recovered in 2009 very close to where A. deyiremeda was unearthed. The bones suggest a creature with a flexible foot and big toe capable of grasping objects, similar to a more primitive hominin called Ardipithecus ramidus, dated to 4.4 million years ago. But perplexingly, the foot bones at Burtele date back to just 3.4 million years ago: the same time period as A. deyiremeda. It’s a combination of proximity in both space and time that cannot be ignored, Kimbel says. “Figuring out whether or not that very primitive foot is the same critter as the clear australopithecine teeth and jaws that are being described now is of utmost importance,” Kimbel says. “It would mean that you could have australopithecus-like heads with more diverse options for locomotion – which is not a picture we have painted so far.”
According to the article, the newly discovered species might ingest more ______ than Lucy’s species.
- A water
- B salt
- C fruit
- D vegetable
- E meat
思路引導 VIP
請觀察文中對於新物種與露西在「生理構造」上的差異描述，特別是關於牙齒大小的部分。接著思考一下：在演化過程中，生物的牙齒尺寸與咀嚼肌肉的改變，通常與牠們日常生活中哪一項最重要的行為活動（Survival behavior）有關？這項改變可能暗示牠們在處理食物的『軟硬程度』或『種類』上，與前輩有什麼不同？
🤖
AI 詳解
AI 專屬家教
牙齒構造與飲食的演化關聯
太棒了！你能精準捕捉到文中關於牙齒構造與飲食習慣的關聯，代表你具備優秀的資訊檢索與推論能力。這題的關鍵在於文中提到的解剖學證據：新發現的「德氏南猿」（Australopithecus deyremeda）牙齒普遍比露西（Lucy）所屬的「阿法南猿」（A. afarensis）還要小。研究員 Fred Spoor 在文中明確指出，較小的牙齒通常與「攝取更多肉類」的飲食（meaty diet）有關，這正是選擇 (E) 的核心依據。
跨學科的推論挑戰
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