Ikigai Daily
WonderPolar physiology fact1,782 of 1,961

Crocodile icefish are the only known vertebrates without functional haemoglobin in adulthood, surviving in oxygen-rich polar water with major circulatory adaptations.

The vertebrate with white blood

OceanBiologyEvolution

Why it matters

The idea in context

Cold seawater holds more dissolved oxygen, but losing haemoglobin is still an extreme evolutionary gamble. Icefish compensate with large hearts, wide blood vessels, high blood volume and scaleless skin that can assist gas exchange. Their success is exquisitely local: a body redesigned around a cold, oxygenated ocean that climate change is now altering.

Türkçe

Aynı kart, başka bir dilde.

Timsah buz balıkları, yetişkinlikte işlevsel hemoglobini olmayan bilinen tek omurgalılardır; oksijence zengin kutup suyunda büyük dolaşım uyarlanmalarıyla yaşarlar.
Beyaz kanlı omurgalı

Soğuk deniz suyu daha fazla çözünmüş oksijen tutar; yine de hemoglobini kaybetmek aşırı bir evrimsel kumardır. Buz balıkları büyük kalp, geniş damar, yüksek kan hacmi ve gaz alışverişine yardım edebilen pulsuz deriyle telafi eder. Başarıları son derece yereldir: iklim değişikliğinin şimdi dönüştürdüğü soğuk ve oksijenli bir okyanusa göre yeniden tasarlanmış beden.

Source trail

Read beyond the card.

Background reading: ChannichthyidaeAttribution and context are revised when stronger evidence appears. Corrections are welcome through the editorial page.
Open in the iPhone appEditorial method

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