eutherian

简明释义

英[juːˈθɪərɪən]美[jʊˈθɪriən]

adj. 真哺乳亚纲的

n. 真兽亚纲动物

英英释义

单词用法

同义词

反义词

例句

1.Sucking lice are exclusively hematophagous ectoparasites of eutherian (placental) mammals, and are worldwide distribution.

吸虱是寄生于真兽类哺乳动物体表的专性吸血寄生虫，广布于世界各地。

2.Sucking lice are exclusively hematophagous ectoparasites of eutherian (placental) mammals, and are worldwide distribution.

吸虱是寄生于真兽类哺乳动物体表的专性吸血寄生虫，广布于世界各地。

3.Before Juramaia's discovery, the oldest known eutherian was Eomaia that lived 125 million years ago.

在发现Juramaia前，已知的最早的真兽类动物是生活在1.25亿年前的Eomaia。

4.The reproductive strategies of eutherian 有胎盘的 mammals are more complex than those of marsupials.

有胎盘的哺乳动物的生殖策略比有袋类动物更复杂。

5.In terms of evolutionary biology, eutherian 有胎盘的 mammals represent a significant adaptation to terrestrial life.

在进化生物学中，有胎盘的哺乳动物代表了对陆地生活的重大适应。

6.Humans are classified as eutherian 有胎盘的 mammals due to their unique placental development.

人类被归类为有胎盘的哺乳动物，因为他们独特的胎盘发育。

7.The fossil record shows that eutherian 有胎盘的 mammals have been around for over 100 million years.

化石记录显示，有胎盘的哺乳动物已经存在超过一亿年。

8.Researchers study the genomes of eutherian 有胎盘的 mammals to understand their evolutionary relationships.

研究人员研究有胎盘的哺乳动物的基因组，以理解它们的进化关系。

作文

The study of mammals is a fascinating field that reveals much about the evolution and diversity of life on Earth. Among the various classifications of mammals, one particularly interesting group is the eutherian mammals, also known as placental mammals. These creatures are characterized by their complex reproductive system, which allows for a longer gestation period compared to other types of mammals, such as marsupials and monotremes. This extended gestation enables eutherian mammals to give birth to more developed young, providing them with a better chance of survival in their respective environments. Eutherians include a wide variety of species, from humans and elephants to whales and bats. The diversity within this group is remarkable, as they have adapted to different habitats and lifestyles. For instance, while some eutherian mammals, like the cheetah, have evolved to be incredibly fast runners, others, such as the sloth, have developed a slow-paced lifestyle that suits their arboreal existence. This adaptability is a testament to the evolutionary success of eutherian mammals and their ability to thrive in various ecological niches. One of the most significant advantages of being a eutherian mammal is the ability to nurture offspring in a protective womb. This not only shields the developing fetus from environmental hazards but also allows for a more efficient transfer of nutrients and oxygen through the placenta. The placenta is an extraordinary organ that forms during pregnancy and serves as a lifeline for the embryo, facilitating the exchange of waste products and nutrients between the mother and her young. This unique reproductive strategy has contributed to the success of eutherian mammals, allowing them to populate diverse ecosystems across the globe. Moreover, eutherian mammals exhibit a wide range of social behaviors and reproductive strategies. Some species, such as elephants, are known for their strong familial bonds and social structures, while others, like many rodents, may lead more solitary lives. The social dynamics of eutherian mammals can significantly influence their reproductive success and survival rates. For example, cooperative breeding in certain species can enhance the survival of young by ensuring that they receive ample care and protection from predators. In addition to their biological and behavioral traits, eutherian mammals play crucial roles in their ecosystems. They often serve as key predators, prey, or pollinators, contributing to the balance of their environments. For example, large herbivorous eutherian mammals like deer help shape plant communities by grazing, while carnivorous species maintain the population dynamics of their prey. This interconnectedness highlights the importance of conserving eutherian mammals and their habitats, as their decline can have cascading effects on entire ecosystems. In conclusion, eutherian mammals represent an essential and diverse group within the animal kingdom. Their unique reproductive adaptations, social behaviors, and ecological roles underscore their significance in understanding the complexities of life on Earth. As we continue to explore and study these remarkable creatures, we gain valuable insights into the evolutionary processes that have shaped the biodiversity we see today. Protecting eutherian mammals and their habitats should be a priority for conservation efforts, ensuring that future generations can appreciate and learn from these incredible animals.

对哺乳动物的研究是一个迷人的领域，它揭示了地球生命的进化和多样性。在各种哺乳动物的分类中，有一个特别有趣的群体，即有胎盘哺乳动物，也称为胎盘哺乳动物。这些生物的特点是其复杂的生殖系统，与其他类型的哺乳动物（如有袋类和单孔类）相比，允许更长的妊娠期。这种延长的妊娠使得有胎盘哺乳动物能够生出发育更完善的幼崽，为它们在各自环境中生存提供了更好的机会。 有胎盘哺乳动物包括从人类和大象到鲸鱼和蝙蝠的各种物种。这个群体内的多样性令人惊叹，因为它们已经适应了不同的栖息地和生活方式。例如，某些有胎盘哺乳动物（如猎豹）进化成为极其快速的奔跑者，而其他如树懒的物种则发展出一种适合其树栖生活的缓慢生活方式。这种适应能力是有胎盘哺乳动物进化成功的证明，使它们能够在各种生态位中繁衍生息。 作为有胎盘哺乳动物的一个重要优势是能够在保护性的子宫中养育后代。这不仅保护了发育中的胎儿免受环境危害，还允许通过胎盘更有效地转移营养和氧气。胎盘是妊娠期间形成的非凡器官，作为胚胎的生命线，促进母亲与幼崽之间废物和营养的交换。这种独特的生殖策略促进了有胎盘哺乳动物的成功，使它们能够遍布全球多样的生态系统。 此外，有胎盘哺乳动物表现出广泛的社会行为和生殖策略。一些物种，如大象，以其强大的家庭纽带和社会结构而闻名，而另一些物种，如许多啮齿动物，则可能过着更加孤独的生活。有胎盘哺乳动物的社会动态可以显著影响它们的繁殖成功和生存率。例如，某些物种中的合作繁殖可以通过确保幼崽获得充足的照顾和保护来增强生存率。 除了它们的生物学和行为特征外，有胎盘哺乳动物在其生态系统中扮演着至关重要的角色。它们通常作为关键的捕食者、猎物或授粉者，促进了其环境的平衡。例如，大型草食性有胎盘哺乳动物（如鹿）通过吃草帮助塑造植物群落，而肉食性物种则维持着猎物的种群动态。这种相互联系强调了保护有胎盘哺乳动物及其栖息地的重要性，因为它们的衰退可能会对整个生态系统产生连锁反应。 总之，有胎盘哺乳动物代表了动物王国中的一个重要而多样化的群体。它们独特的生殖适应、社会行为和生态角色突显了它们在理解地球生命复杂性方面的重要性。随着我们继续探索和研究这些非凡的生物，我们获得了对塑造今天所见生物多样性的进化过程的宝贵见解。保护有胎盘哺乳动物及其栖息地应成为保护工作的一项优先事项，以确保未来几代人能够欣赏和学习这些令人难以置信的动物。