Life originated in the early seas less than a billion years after the Earth was formed. Yet another three billion years were to pass before the first plants and animals appeared on the continents. Life’s transition from the sea to the land was perhaps as much of an evolutionary challenge as was the genesis of life. What forms of life were able to make such a drastic change in lifestyle? The traditional view of the first terrestrial organisms is based on mega fossils-relatively large ...
Nguyễn Thị Thương | Chat Online | |
06/09 15:37:14 (Tiếng Anh - Lớp 12) |
Life originated in the early seas less than a billion years after the Earth was formed. Yet another three billion years were to pass before the first plants and animals appeared on the continents. Life’s transition from the sea to the land was perhaps as much of an evolutionary challenge as was the genesis of life. What forms of life were able to make such a drastic change in lifestyle? The traditional view of the first terrestrial organisms is based on mega fossils-relatively large specimens of essentially whole plants and animals. Vascular plants, related to modern seed plants and ferns, left the first comprehensive mega fossil record. Because of this, it has been commonly assumed that the sequence of terrestrialization reflected the evolution of modern terrestrial ecosystems. In this view, primitive vascular plants first colonized the margins of continental waters, followed by animals that feed on the plants, and lastly by animals that preyed on the plant-eaters. Moreover, the mega fossils suggest that terrestrial life appeared and diversified explosively near the boundary between the Silurian and the Devonian periods, a little more than 400 million years ago. Recently, however, paleontologists have been taking a closer look at the sediments below this Silurian-Devonian geological boundary. It turns out that some fossils can be extracted from these sediments by putting the rocks in an acid bath. The technique has uncovered new evidence form sediments that were deposited near the shores of the ancient oceans- plant microfossils and microscopic pieces of small animals. In many instances the specimens are less than one-tenth of a millimeter in diameter. Although they were entombed in the rocks for hundreds of millions of years, many of them fossils consist of the organic remains of the organism. These newly discovered fossils have not only revealed the existence of previously unknown organisms, but have also pushed back these dates for the invasion of land by multicellular organisms. Our views about the nature of the early plant and animal communities are now being revised. And with those revisions come new speculations about the first terrestrial life-forms
In what order did the organisms first appear on earth?
Lựa chọn một trả lời để xem Đáp án chính xác Báo sai đáp án hoặc câu hỏi |
A. vascular plants, plant-eating animals, carnivores 0 % | 0 phiếu |
B. carnivores, plant-eaters, megafossils 0 % | 0 phiếu |
C. mega fossils, prey hunters, plant-eaters 0 % | 0 phiếu |
D. seed plants, ferns, megafossils 0 % | 0 phiếu |
Tổng cộng: | 0 trả lời |
Trắc nghiệm liên quan
- Life originated in the early seas less than a billion years after the Earth was formed. Yet another three billion years were to pass before the first plants and animals appeared on the continents. Life’s transition from the sea to the land was ... (Tiếng Anh - Lớp 12)
- Life originated in the early seas less than a billion years after the Earth was formed. Yet another three billion years were to pass before the first plants and animals appeared on the continents. Life’s transition from the sea to the land was ... (Tiếng Anh - Lớp 12)
- Life originated in the early seas less than a billion years after the Earth was formed. Yet another three billion years were to pass before the first plants and animals appeared on the continents. Life’s transition from the sea to the land was ... (Tiếng Anh - Lớp 12)
- Life originated in the early seas less than a billion years after the Earth was formed. Yet another three billion years were to pass before the first plants and animals appeared on the continents. Life’s transition from the sea to the land was ... (Tiếng Anh - Lớp 12)
- Life originated in the early seas less than a billion years after the Earth was formed. Yet another three billion years were to pass before the first plants and animals appeared on the continents. Life’s transition from the sea to the land was ... (Tiếng Anh - Lớp 12)
- Animals have an intuitive awareness of quantities. They know without analysis the difference between a number of objects and a smaller number. In his book “ The natural History of Selboure ” (1786 ) , the naturalist Gilbert White tells how he ... (Tiếng Anh - Lớp 12)
- Animals have an intuitive awareness of quantities. They know without analysis the difference between a number of objects and a smaller number. In his book “ The natural History of Selboure ” (1786 ) , the naturalist Gilbert White tells how he ... (Tiếng Anh - Lớp 12)
- Animals have an intuitive awareness of quantities. They know without analysis the difference between a number of objects and a smaller number. In his book “ The natural History of Selboure ” (1786 ) , the naturalist Gilbert White tells how he ... (Tiếng Anh - Lớp 12)
- Animals have an intuitive awareness of quantities. They know without analysis the difference between a number of objects and a smaller number. In his book “ The natural History of Selboure ” (1786 ) , the naturalist Gilbert White tells how he ... (Tiếng Anh - Lớp 12)
- Animals have an intuitive awareness of quantities. They know without analysis the difference between a number of objects and a smaller number. In his book “ The natural History of Selboure ” (1786 ) , the naturalist Gilbert White tells how he ... (Tiếng Anh - Lớp 12)
Trắc nghiệm mới nhất
- Để đọc các thông tin liên quan đến bóng đá trên website báo Tiền Phong, em chọn mục nào trên bảng chọn nội dung được đặt ở đầu trang? (Tin học - Lớp 5)
- A. PHẦN TRẮC NGHIỆM (7,0 điểm) Câu 1. (1,0 điểm) (M1) Khoanh vào câu trả lời đúng nhất. Thành phần nào của website thể hiện cách phân loại thông tin theo các chủ đề? (Tin học - Lớp 5)
- A. PHẦN TRẮC NGHIỆM (7,0 điểm) Câu 1. (1,0 điểm) (M1) Khoanh vào câu trả lời đúng nhất. Ứng dụng nào sau đây giúp em tạo sản phẩm số? (Tin học - Lớp 5)
- Trò chơi mê cung là chương trình được viết bằng phần mềm nào? (Tin học - Lớp 5)
- Trong các phần mềm dưới đây, phần mềm nào giúp em chia sẻ thông tin? (Tin học - Lớp 5)
- Trong các phần mềm dưới đây, phần mềm nào giúp em tạo bài trình chiếu? (Tin học - Lớp 5)
- Muốn tìm kiếm thông tin liên quan đến giáo dục trên website báo Thiếu niên Tiền phong và Nhi đồng em nên tìm ở chủ đề nào? (Tin học - Lớp 5)
- A. PHẦN TRẮC NGHIỆM (7,0 điểm) Câu 1. (1,0 điểm) (M1) Khoanh vào câu trả lời đúng nhất. Khi mở của sổ This PC, em sẽ nhìn thấy công cụ tìm kiếm nằm ở vị trí nào? (Tin học - Lớp 5)
- Phần mềm Duolingo giúp em (Tin học - Lớp 5)
- Khi không biết nơi lưu trữ tệp, thư mục, em có thể sử dụng công cụ có sẵn trong cửa sổ phần mềm nào? (Tin học - Lớp 5)