龙存在吗？

Geoffrey Widdison，从六岁起就开始学习科学，现在还在开始。

Geoffrey Widdison, Been learning science since I was six, still getting started.

对此的最佳答案在 XKCD 的这张图表中：

The best answer to this is in this graph from XKCD:


在每个工业化国家，几乎所有人的生命中每一分钟都有摄像头存在。如果某物存在并且可以拍摄，那么现在几乎可以肯定它已经被拍摄了。
如果某物没有可靠的图片，那么它要么是无法观察的（例如人类从未遇到过的深海生物），要么仅在非常贫困的地区发现（出于某种原因），要么非常罕见，以至于人类几乎从未遇到过，或者根本不存在。
龙属于其中一类，你猜是哪一类。

In every industrialized country, almost the entire population has cameras on them every minute of their lives. If something exists and is possible to photograph, it's almost certainly be photographed by now.
If there are no reliable pictures of something then either it isn't observable (such as a deep sea creature that humans never encounter), is found only in very poor areas (for some reason), is so rare that human encounters almost never happen, or simply does not exist.
Dragons are in one of those categories, your guess as to which.

Kas Kramer，龙类专家

Kas Kramer, dragon expert.

遗憾的告诉你，不存在。。
好吧，至少不在这个星球上。如果考虑到宇宙的浩瀚、可以孕育生命的行星的数量，以及这颗行星令人难以置信的多样性，再加上其他星球上存在生命的可能性，龙可能存在于宇宙的其他地方。但这是一个巨大的宇宙，我们很可能永远也找不到它们。
龙并不完全符合正常的进化模式，因为它们显然是有六肢的爬行动物或哺乳动物。只有节肢动物（具有外骨骼的生物，如昆虫和甲壳类动物）有六肢或更多肢体——所有陆地生物的共同祖先是四足，这意味着我们的六肢龙必须自发进化，在原设计为四条腿的骨骼基础上有两个额外的肢体。

Unfortunately, no.
Well, not on this planet. Given the vastness of the universe, the amount of planets that could grow life, and the incredible diversity of this one planet multiplied by the possibility of life on other worlds, they probably exist somewhere else in the universe. But it's a big universe, and chances are we're never going to find them.
Dragons don't exactly fit into the normal pattern of evolution, given the fact that they are apparently reptilian or mammalian creatures with six limbs. Only arthropodic creatures (things with exoskeletons, like insects and crustaceans) have six or more limbs- the common ancestor that gave rise to all land creatures was tetrapodal (four-footed), meaning that our six-limbed dragons would have had to spontaneously evolve two extra limbs in a skeleton designed to have four.

所以这不合理。如果龙是真实的，为什么没有更多的六肢生物？整个进化分支到哪里去了？如果没有任何其他六足爬行动物或哺乳动物的证据，就不可能只存在一条小分支——龙。
还有一个问题是它们将如何飞行，答案是这样的：它们需要真正巨大的翅膀和中空的骨骼结构，以及高效的血液、轻质的身体覆盖物，可能还有气囊来缓冲身体，使其更具空气动力学性能。这意味着龙不会是我们经常在插图中看到的那种轻盈的形状，而是一种更加鱼雷形、更光滑的形状。戏剧性和雄伟程度将远不如我们的想象。
所以不幸的是，我们在地球上的龙类朋友只是神话。但我们仍然可以幻想在银河系的其他地方存在龙。
希望这可以帮到你！

Naturally, this makes no sense. If they were real, why aren't there more creatures with six limbs? Where did that entire branch of evolution go? It wouldn't be possible for only one small branch- dragons- to exist without any other evidence of hexapodal (six-footed) reptiles or mammals.
There's also the question of how would they fly, which is answered so: They would require truly massive wings and a hollow bone structure paired with hyperefficient blood, lightweight body covering, and probably air sacs to buffer the body to be more aerodynamic. This means that dragons wouldn't be the same lithe shape that we often see in illustrations, but it would be a more torpedo-shaped, smooth form. Much less dramatic and much less majestic.
So unfortunately, our draconic friends on planet Earth are so much mythology. But we can still dream about them elsewhere in the galaxy.
Hope this helps!

Clarence Sherrick，在拉斯维加斯的心灵之眼工作

Clarence Sherrick, works at Psychic Eye, Las Vegas

其中经典的龙其实是一种会飞的爬行动物。就像翼龙，而这样的生物确实存在。最大的翼龙被称为风神翼龙，翼展比小型飞机还大。龙会喷火的部分可能只是一个幻想。尽管已经有人提供了一些关于喷火在物理上如何可行的逻辑解释，但我仍然严重怀疑。恐龙被认为在 6500-6600万年前完全灭绝，主要是因为小行星撞击地球以及其他可知的后果进一步加剧了恐龙的灭绝。从技术上讲，恐龙并没有完全灭绝，现代的鸟类被认为是恐龙的后代。
有几个被认为已灭绝的生物在现代被重新发现的例子。最著名的是腔棘鱼，一种古老的史前鱼类。此外，还有一些过去认为灭绝的动物也已被发现。

of theseThe classic dragon was actually a flying reptile. A Pterosaur. And such creatures did exist. The largest is called Quetzalcoatalus and had a wing span larger than a small plane. The fire breathing part may only be a fantasy. Although some logical explanations have been offered as to how this might have been physically possible. Although I seriously doubt it. The dinosaurs are believed to have gone totally extinct 65-66 million years ago primarily because of an asteroid collision with the Earth along with other discernable after effects/causes that further exacerbated the extintion. Technically, they did not go fully extinct as birds are now considered living descendants of the dinosaurs.
There have been several examples of creatures believed to have gone extinct being rediscovered in the modern era. The most famous is the coelacanth..an ancient prehistoric fish. Moreover,quite a few of these have been found.

有人提出，尼斯湖水怪很可能是一只幸存的蛇颈龙，它以某种方式逃脱了灭绝，并发生了进化，能在尼斯湖的冷水环境中生存。由于气候变化和地质构造活动，它被限制在这片水域中。关于尼斯湖水怪的许多描述似乎与经典的蛇颈龙形象非常匹配。但即使它真的存在，人类也仍未确定尼斯湖水怪的实际栖息地。
然而，凯尔特人、中国人和亚瑟王神话中的龙更可能是幻想而非现实。可以设想很久以前，人类就发现了一些恐龙遗骸，并将几个物种的各个部分组合在一起，形成了传说中的经典龙形象。让我简洁地回答你的问题：是的，曾经有龙。人类将他们的记忆与古老的恐怖生物联系起来。龙是地球上曾存在过的最凶猛的生物，其中一些实际上会飞。