Episode 4.5 · 14 min

Snowball Earth

The evidence for the Cryogenian ice ages, the feedbacks that froze and thawed Earth, and the refuges where life may have endured.

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Visual credits

10 sources

Sources and credits for imagery used in this film, including material incorporated into explanatory animations.

Tillite (Elatina Formation, Neoproterozoic; Enorama Creek section, Flinders Ranges, South Australia) 10
James St. John
View original source ↗Source licence: CC BY 2.0
Cryogenian-Ediacaran boundary (Nuccaleena Formation over Elatina Formation, Neoproterozoic; Enorama Creek section, Flinders Ranges, South Australia) 3
James St. John
View original source ↗Source licence: CC BY 2.0
Incorporated into an explanatory animation; presentation may include cropping, labels and overlays.
Songluo Biota palaeogeography — Figure 1 excerpt centred on panel a
Huyue Song, Zhihui An, Qin Ye, Eva E. Stüeken, Jing Li, Jun Hu, Thomas J. Algeo, Li Tian, Daoliang Chu, Haijun Song, Shuhai Xiao, Jinnan Tong; map credited to S. Zhang et al. (2013), reference 26 in the source article
View original source ↗Source licence: CC BY 4.0
Incorporated into an explanatory animation; presentation may include cropping, labels and overlays.
Songluo Biota fossils — Figure 1c excerpt
Huyue Song, Zhihui An, Qin Ye, Eva E. Stüeken, Jing Li, Jun Hu, Thomas J. Algeo, Li Tian, Daoliang Chu, Haijun Song, Shuhai Xiao, Jinnan Tong; panel c modified from Q. Ye et al. (2019), reference 32 in the source article
View original source ↗Source licence: CC BY 4.0
Incorporated into an explanatory animation; presentation may include cropping, labels and overlays.
Meltwater ponds on George VI (50979868352)
Julien Seguinot from Lille, France
View original source ↗Source licence: CC BY-SA 2.0
Incorporated into an explanatory animation; presentation may include cropping, labels and overlays.
Meltwater Ponds on the Amery Ice Shelf (153841 - oli 20250101 lrg)
NASA Earth Observatory images by Wanmei Liang, using Landsat data from the U.S. Geological Survey. Story by Kathryn Hansen.
View original source ↗Source licence: Public domain
Incorporated into an explanatory animation; presentation may include cropping, labels and overlays.
Marinoan deglaciation — Figure 2 excerpt centred on panel D, annotated outcrop photograph
Adrian R. Tasistro-Hart, Francis A. Macdonald, James L. Crowley, Mark D. Schmitz
View original source ↗Source licence: CC BY 4.0
Incorporated into an explanatory animation; presentation may include cropping, labels and overlays.
McMurdo Ice Shelf near Bratina Island — Lezcano et al., Figure 1 photographs B and D
María Ángeles Lezcano, Laura Sánchez-García, Antonio Quesada, Daniel Carrizo, Miguel Ángel Fernández-Martínez, Erika Cavalcante-Silva, Víctor Parro
View original source ↗Source licence: CC BY 4.0
Cropped photographic panels; resized, framed, and placed with editorial locality labels. Photographic content was not generated or redrawn.
Microbial mats in Garwood Valley, Antarctica — Mercado-Juárez et al., Figure 1C
Ricardo A. Mercado-Juárez, Patricia M. Valdespino-Castillo, Martín Merino Ibarra, Silvia Batista, Walter Mac Cormack, Lucas Ruberto, Edward J. Carpenter, Douglas G. Capone, Luisa I. Falcón
View original source ↗Source licence: CC BY 4.0
Cropped photographic panels; resized, framed, and placed with editorial locality labels. Photographic content was not generated or redrawn.
Natural Earth 1:110m country polygons; Antarctica feature only
Natural Earth contributors
View original source ↗Source licence: Public domain
Original south-polar locator drawing from Antarctica polygons. Bratina Island locator at 78 degrees S, 165 degrees 35 minutes E, using the location reported by Lezcano et al.

Research references

Selected sources from the episode’s research and scientific figures.

Music

Meditation From The Star Orion
OctahedronMusic · Envato Elements

Footage and image usage

Credits and usage times retained from the published edition or its production credit record. Where present, times identify visual appearances, not documentary chapters. Source and licence corrections are listed in the visual credits above.

James St. John - 2:58-3:06, Tillite (Elatina Formation, Neoproterozoic; Enorama Creek
Custom animations and figures: From Cosmos to Civilization. Third-party material incorporated into animations is credited on the linked sources page.

How this film was made

Created and editorially directed by Anders Lunde using a custom production system developed over six months. AI assists research, drafting, programming, and visual production; I review and edit the material and make the final editorial decisions. Narration uses text-to-speech. Visuals combine custom-built scientific animations, AI-generated reconstructions, and credited scientific imagery.

Generated reconstructions illustrate scientific interpretations. They are distinct from photographs, specimens, and measured data.

More about the creator and production →

Visual credits

Tillite (Elatina Formation, Neoproterozoic; Enorama Creek section, Flinders Ranges, South Australia) 10

Cryogenian-Ediacaran boundary (Nuccaleena Formation over Elatina Formation, Neoproterozoic; Enorama Creek section, Flinders Ranges, South Australia) 3

Songluo Biota palaeogeography — Figure 1 excerpt centred on panel a

Songluo Biota fossils — Figure 1c excerpt

Meltwater ponds on George VI (50979868352)

Meltwater Ponds on the Amery Ice Shelf (153841 - oli 20250101 lrg)

Marinoan deglaciation — Figure 2 excerpt centred on panel D, annotated outcrop photograph

McMurdo Ice Shelf near Bratina Island — Lezcano et al., Figure 1 photographs B and D

Microbial mats in Garwood Valley, Antarctica — Mercado-Juárez et al., Figure 1C

Natural Earth 1:110m country polygons; Antarctica feature only

Research references

Music

How this film was made