SciShow
Atavisms: 4 Lost Traits That Returned
Every once in a while, traits thought to be lost forever suddenly reappear, like a dolphin or a whale born with complete hind limbs! Known as atavisms, these occurrences can teach us all sorts of things, like how limbs actually grow.
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Humpback whale (Megaptera novaeangliae) pectoral fin, Iceland, N Atlantic
Humpback whale (Megaptera novaeangliae) pectoral fin, Iceland, N Atlantic
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A humpback whale (Megaptera Novaeangliae) in the North Pacific Ocean engages in lobtailing, slapping its flukes on the surface of the water.
A humpback whale (Megaptera Novaeangliae) in the North Pacific Ocean engages in lobtailing, slapping its flukes on the surface of the water.
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A humpback whale (Megaptera Novaeangliae) slaps the surface of the water with one of it's pectoral fins. Possible reasons for this behavior, known as pec slapping, include dislodging parasites, stunning prey, or simply play.
A humpback whale (Megaptera Novaeangliae) slaps the surface of the water with one of it's pectoral fins. Possible reasons for this behavior, known as pec slapping, include dislodging parasites, stunning prey, or simply play.
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Pod of orcas (Orcinus orca) surfacing in unison, Antarctica
Pod of orcas (Orcinus orca) surfacing in unison, Antarctica
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WA River dolphin surfacing and diving underwater again, South America
WA River dolphin surfacing and diving underwater again, South America
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MS POV Spinner dolphins bow riding / Caribbean, Dominica
MS POV Spinner dolphins bow riding / Caribbean, Dominica
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Sperm Whale - pov boat, CU back disappearing into water, tail rises in air & disappears into water, sea horizon, blue sky with white cloud
Sperm Whale - pov boat, CU back disappearing into water, tail rises in air & disappears into water, sea horizon, blue sky with white cloud
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Minke whale (Balaenoptera acutorostrata) dancing around research vessel, good sound (2002). St Lawrence, Canada.
Minke whale (Balaenoptera acutorostrata) dancing around research vessel, good sound (2002). St Lawrence, Canada.
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small pod of Common dolphins (Delphinus sp.) weave right to left in front of and past camera then small red bait ball passes close up on right of frame.. Gibraltar, Mediterranean
small pod of Common dolphins (Delphinus sp.) weave right to left in front of and past camera then small red bait ball passes close up on right of frame.. Gibraltar, Mediterranean
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MS TS Sperm whale pair swimming and descending / Caribbean, Dominica
MS TS Sperm whale pair swimming and descending / Caribbean, Dominica
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Red bait ball and small pod of Common dolphins (Delphinus sp.) passing through hazy water, Gibraltar, Mediterranean
Red bait ball and small pod of Common dolphins (Delphinus sp.) passing through hazy water, Gibraltar, Mediterranean
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Floating baleen and upper lip of whale, St Lawrence, Canada.
Floating baleen and upper lip of whale, St Lawrence, Canada.
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Humpback whale (Megaptera novaeangliae) full breach, Iceland, N Atlantic
Humpback whale (Megaptera novaeangliae) full breach, Iceland, N Atlantic
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Red bait ball and small pod of Common dolphins (Delphinus sp.) passing through hazy water, Gibraltar, Mediterranean
Red bait ball and small pod of Common dolphins (Delphinus sp.) passing through hazy water, Gibraltar, Mediterranean
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Humpback whale (Megaptera novaeangliae breaching), Iceland, N Atlantic
Humpback whale (Megaptera novaeangliae breaching), Iceland, N Atlantic
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Humpback whale (Megaptera novaeangliae) breaching, Iceland, N Atlantic
Humpback whale (Megaptera novaeangliae) breaching, Iceland, N Atlantic
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Bottlenose Dolphins - underwater, topshot, head swims below, mother & baby swim away from camera in sunny shallows, both surface to breathe, good dappled sunlight
Bottlenose Dolphins - underwater, topshot, head swims below, mother & baby swim away from camera in sunny shallows, both surface to breathe, good dappled sunlight
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MWA Humpback Whale (Megaptera novaeangliae) breaching and splashing back in to water, Tonga
MWA Humpback Whale (Megaptera novaeangliae) breaching and splashing back in to water, Tonga
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MCU Humpback Whale (Megaptera novaeangliae) moving through water, swirling tail to camera, underwater, Tonga
MCU Humpback Whale (Megaptera novaeangliae) moving through water, swirling tail to camera, underwater, Tonga
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Humpback whale (Megaptera novaeangliae) breaching, Iceland, N Atlantic
Humpback whale (Megaptera novaeangliae) breaching, Iceland, N Atlantic
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A humpback whale (Megaptera Novaeangliae), swims close to the surface, spouts, and disappears into the blue depths of the Pacific Ocean.
A humpback whale (Megaptera Novaeangliae), swims close to the surface, spouts, and disappears into the blue depths of the Pacific Ocean.