北极熊是本图谱二十四种之一。不是商品目录，而是把演化、解剖、行为、文化、象征、保护与分布写成一套体系。
分数是速度、智力、分布、韧性、文化影响与生态角色的相对评价，不是实验室排名。
七章分别写起源与演化、身体与感官、生活与行为、文化、传说象征、保护压力，以及与人重叠的分布。
深度导读
北极熊 is not a single postcard animal. It is a set of populations, subspecies and human rules inside the wildlife family of this atlas.
多样性、身体、文化与分布 — 加上针对本语言区的视角。
Field guides collapse many lineages into the English word 北极熊. Subspecies, flyways and captive lines do not share one fate -- bald eagles and Philippine eagles, or western and mountain gorillas, are the caution.
This atlas picks a Wikipedia title as the hero image and then keeps the rest of the grade in view so a recovered stock cannot launder a CR cousin.
A long-skulled ursid with huge forepaws, black skin under hollow guard hairs, and a gut built for seal fat. It is a marine mammal in habit, a bear in clade.
Still-hunt at seal holes and break-in on birth lairs. Fat, not lean meat, pays the ice year. Onshore summers are a deficit for many stocks.
English-language culture met the 北极熊 through film, law, heraldry and zoos. Those portrayals move money and sometimes take; they are not a field census.
The culture chapter dates posters and statutes so a 1975 film or a 1961 logo cannot pretend to be a 2020s Red List.
Vulnerable. The 2008 US ESA listing treated sea-ice loss as the primary threat -- a climate instrument more than a hunt story.
Tourism, conflict payments, quotas and captive loans are dated economic bands in the market chapter -- not live prices and not a best-species prize.
生命科学深潜
北极熊 biology is a stack of structure, energy, sensing and hard limits. The four sections below are the same headings used across the atlas so types can be compared without a best-species frame.
解剖、感官、行为与限度 — 加上本地区的田野用语。
A long-skulled ursid with huge forepaws, black skin under hollow guard hairs, and a gut built for seal fat. It is a marine mammal in habit, a bear in clade.
Load paths and tissues (not metals) are expanded in the anatomy chapter.
Still-hunt at seal holes and break-in on birth lairs. Fat, not lean meat, pays the ice year. Onshore summers are a deficit for many stocks.
The how-it-works diagrams reduce that budget to a six-node loop.
Smell through ice and a patience that looks like stillness. Vision is secondary to a hole in the ice.
Control here means the animal steering itself -- not a vehicle ECU.
Ice-season length. A stable stock in one basin does not retire a VU card written on a melt curve.
Resilience scores encode those limits relative to the other 23 types.
本种的授权照片 — 主图、时代与象征在同一面墙。
同类群、不同分数 — 选一场对决。
六轴上最近的邻居 — 速度、智力、分布、韧性、文化与生态角色。