Phrases in bold are the first few words of the sentence in the text to which the citation applies.

Epigraph

Choose to be puzzled: Will Kyselka, An Ocean in Mind (University of Hawaii Press, 1987).

Prologue: Paradise Lost

Deep ice cores from Greenland: J. P. Steffensen et al., “High-Resolution Greenland Ice Core Data Show Abrupt Climate Change Happens in Few Years,” Science 321, no. 5889 (August 1, 2008): 680–84, https://doi.org/10.1126/science.1157707.
Answers were so hard to find: W Berger, “The Younger Dryas Cold Spell—a Quest for Causes,” Palaeogeography, Palaeoclimatology, Palaeoecology 89, no. 3 (December 1, 1990): 219–37, https://doi.org/10.1016/0031-0182(90)90063-D.
Then in 2007: R.B. Firestone, “Evidence for an Extraterrestrial Impact Event 12,900 Years Ago That Contributed to Megafaunal Extinctions and the Younger Dryas Cooling,” 2007, http://abstractsearch.agu.org/meetings/2007/SM/PP43A-01.html.
It did not take long: Nicholas Pinter and Scott E. Ishman, “Impacts, Megatsunami, and Other Extraordinary Claims,” GSA Today 18, no. 1 (January 2008): 37, https://doi.org/10.1130/GSAT01801GW.1.

1. The Cycle of Cosmic Catastrophes

The reading public: Richard Firestone, Allen West, and Simon Warwick-Smith, The Cycle of Cosmic Catastrophes: How a Stone-Age Comet Changed the Course of World Culture (Bear & Company, 2006).
The title of their article: Firestone, R. B., and Topping, W. 2001. “Terrestrial Evidence of a Nuclear Catastrophe in Paleoindian Times.” Mammoth Trumpet.
A supernova: G. Robert Brakenridge, “Terrestrial Paleoenvironmental Effects of a Late Quaternary-Age Supernova,” Icarus 46, no. 1 (April 1981): 81–93, https://doi.org/10.1016/0019-1035(81)90077-4.

2. The Younger Dryas Impact Hypothesis

In October: Firestone, “Evidence for an Extraterrestrial Impact Event 12,900 Years Ago That Contributed to Megafaunal Extinctions and the Younger Dryas Cooling.”
Always, we find the Clovis artifacts: Firestone, West, and Warwick-Smith, The Cycle of Cosmic Catastrophes.
No skeleton of extinct megafauna: Firestone, West, and Warwick-Smith.

3. Testing Hypotheses

At first: Spencer R. Weart, The Discovery of Global Warming (Harvard University Press, 2009); James Lawrence Powell, Four Revolutions in the Earth Sciences; from Heresy to Truth (Columbia University Press, New York, NY, 2015).

4. Dead on Arrival?

Nicholas Pinter and Scott Ishman titled their article: Pinter, Nicholas, and Scott E. Ishman. 2008. “Impacts, Mega-Tsunami, and Other Extraordinary Claims.” GSA Today 18 (1): 37. https://doi.org/10.1130/GSAT01801GW.1.
Kerr followed up: R. A. Kerr, “PALEONTOLOGY: Experts Find No Evidence for a Mammoth-Killer Impact,” Science 319, no. 5868 (March 7, 2008): 1331–32, https://doi.org/10.1126/science.319.5868.1331.
Kerr now found: R. A. Kerr, “PLANETARY IMPACTS: Did the Mammoth Slayer Leave a Diamond Calling Card?,” Science 323, no. 5910 (January 2, 2009): 26–26, https://doi.org/10.1126/science.323.5910.26.
By the time of Kerr’s next report: D. J. Kennett et al., “Nanodiamonds in the Younger Dryas Boundary Sediment Layer,” Science 323, no. 5910 (January 2, 2009): 94–94, https://doi.org/10.1126/science.1162819.
Richard Firestone did not attend: David Morrison, “Did a Cosmic Impact Kill the Mammoths,” Skeptical Inquirer 34, no. May/June (2010): 8.
The title: R. A. Kerr, “Mammoth-Killer Impact Flunks Out,” Science 329, no. 5996 (September 3, 2010): 1140–41, https://doi.org/10.1126/science.329.5996.1140.
According to a 2010 review of impact criteria: Bevan M. French and Christian Koeberl, “The Convincing Identification of Terrestrial Meteorite Impact Structures: What Works, What Doesn’t, and Why,” Earth-Science Reviews 98, no. 1–2 (January 1, 2010): 123–70, https://doi.org/10.1016/j.earscirev.2009.10.009.
The PBS website includes a complete transcript: “Megabeasts’ Sudden Death — NOVA | PBS,” accessed October 21, 2018, http://www.pbs.org/wgbh/nova/evolution/last-extinction.html.

5. An Independent Evaluation

Moving back in time: T. A. Surovell et al., “An Independent Evaluation of the Younger Dryas Extraterrestrial Impact Hypothesis,” Proceedings of the National Academy of Sciences 106, no. 43 (October 27, 2009): 18155–58, https://doi.org/10.1073/pnas.0907857106.

6. A Cautionary Tale

William Mahaney and colleagues: William C. Mahaney, David Krinsley, and Volli Kalm, “Evidence for a Cosmogenic Origin of Fired Glaciofluvial Beds in the Northwestern Andes: Correlation with Experimentally Heated Quartz and Feldspar,” Sedimentary Geology 231, no. 1–2 (November 2010): 31–40, https://doi.org/10.1016/j.sedgeo.2010.08.004.
At the Clovis site at Sheridan Cave, Ohio: Brian G Redmond and Kenneth B Tankersley, “Species Response to the Theorized Clovis Comet 1 Impact at Sheriden Cave, Ohio” 28 (2011): 3.
As we saw: Andrei V Kurbatov et al., “Discovery of a Nanodiamond-Rich Layer in the Greenland Ice Sheet,” August 2010, 11.
The article, published in 2011 in Earth Science Reviews: Nicholas Pinter et al., “The Younger Dryas Impact Hypothesis: A Requiem,” Earth-Science Reviews 106, no. 3–4 (June 2011): 247–64, https://doi.org/10.1016/j.earscirev.2011.02.005.
Consider these examples: Powell, Four Revolutions in the Earth Sciences; from Heresy to Truth.
Langmuir and Hall (1989) refers to an article: Irving Langmuir and Robert N. Hall, “Pathological Science,” Physics Today 42, no. 10 (October 1989): 36–48, https://doi.org/10.1063/1.881205.
Gratzer's book: Walter Gratzer, The Undergrowth of Science: Delusion, Self-Deception, and Human Frailty (OUP Oxford, 2001).
Robert Park's Voodoo Science: Park wrote a second book in the "Voodoo Series": Superstition: Belief in the Age of Science. According to Wikipedia, it was inspired in part by an oak tree that fell on him.

7. Synchrony

A few years after the Alvarez Theory appeared: Charles B. Officer and Charles L. Drake, “The Cretaceous-Tertiary Transition,” Science 219, no. 4591 (1983): 1383–90; Charles B. Officer and Charles L. Drake, “Terminal Cretaceous Environmental Events,” Science 227, no. 4691 (March 8, 1985): 1161–67, https://doi.org/10.1126/science.227.4691.1161.
Not only was the KTB found to be the same age everywhere,: Paul R. Renne et al., “Time Scales of Critical Events around the Cretaceous-Paleogene Boundary,” Science 339, no. 6120 (2013): 684–687.
They reviewed previously reported radiocarbon dates: D. J. Meltzer et al., “Chronological Evidence Fails to Support Claim of an Isochronous Widespread Layer of Cosmic Impact Indicators Dated to 12,800 Years Ago,” Proceedings of the National Academy of Sciences 111, no. 21 (May 27, 2014): E2162–71, https://doi.org/10.1073/pnas.1401150111.
In a 2015 paper in PNAS: James P. Kennett et al., “Bayesian Chronological Analyses Consistent with Synchronous Age of 12,835–12,735 Cal B.P. for Younger Dryas Boundary on Four Continents,” Proceedings of the National Academy of Sciences 112, no. 32 (August 11, 2015): E4344–53, https://doi.org/10.1073/pnas.1507146112.

8: Microspherules

In a 2012 paper: Malcolm A. LeCompte et al., “Independent Evaluation of Conflicting Microspherule Results from Different Investigations of the Younger Dryas Impact Hypothesis,” Proceedings of the National Academy of Sciences 109, no. 44 (October 30, 2012): E2960–69, https://doi.org/10.1073/pnas.1208603109.
In the discussion of methods: Firestone, “Evidence for an Extraterrestrial Impact Event 12,900 Years Ago That Contributed to Megafaunal Extinctions and the Younger Dryas Cooling.”
Using SEM and XRS: Alexandre V. Andronikov et al., “Implications from Chemical, Structural and Mineralogical Studies of Magnetic Microspherules from around the Lower Younger Dryas Boundary (New Mexico, USA),” Geografiska Annaler: Series A, Physical Geography 98, no. 1 (March 2016): 39–59, https://doi.org/10.1111/geoa.12122.
At about the same time as LeCompte et al. published: T. E. Bunch et al., “Very High-Temperature Impact Melt Products as Evidence for Cosmic Airbursts and Impacts 12,900 Years Ago,” Proceedings of the National Academy of Sciences 109, no. 28 (July 10, 2012): E1903–12, https://doi.org/10.1073/pnas.1204453109.
In PNAS in May 2013: James H. Wittke et al., “Evidence for Deposition of 10 Million Tonnes of Impact Spherules across Four Continents 12,800 y Ago,” Proceedings of the National Academy of Sciences 110, no. 23 (June 4, 2013): E2088–97, https://doi.org/10.1073/pnas.1301760110.
Another group found abundant microspherules: C. Vance Haynes et al., “The Murray Springs Clovis Site, Pleistocene Extinction, and the Question of Extraterrestrial Impact,” Proceedings of the National Academy of Sciences 107, no. 9 (March 2, 2010): 4010–15, https://doi.org/10.1073/pnas.0908191107.
It is clear: Wittke et al., “Evidence for Deposition of 10 Million Tonnes of Impact Spherules across Four Continents 12,800 y Ago.”

9. Precious Stones

They found the same level of enrichment: Andronikov et al., “Implications from Chemical, Structural and Mineralogical Studies of Magnetic Microspherules from around the Lower Younger Dryas Boundary (New Mexico, USA).”
Paquay et al. (2009) found weak peaks: Francois S Paquay et al., “Absence of Geochemical Evidence for an Impact Event at the Bølling–Allerød/Younger Dryas Transition,” PNAS 106, no. 51 (December 2009): 6.
In microspherules from Blackwater Draw: Andronikov et al., “Implications from Chemical, Structural and Mineralogical Studies of Magnetic Microspherules from around the Lower Younger Dryas Boundary (New Mexico, USA).”
The report from Bunch et al.,: M. I. Petaev et al., “Large Pt Anomaly in the Greenland Ice Core Points to a Cataclysm at the Onset of Younger Dryas,” Proceedings of the National Academy of Sciences 110, no. 32 (August 6, 2013): 12917–20, https://doi.org/10.1073/pnas.1303924110.
In March 2017: Christopher R. Moore et al., “Widespread Platinum Anomaly Documented at the Younger Dryas Onset in North American Sedimentary Sequences,” Scientific Reports 7 (March 9, 2017): 44031, https://doi.org/10.1038/srep44031.
My take is that the Greenland platinum peak: Wally Broecker, “An Extraterrestrial Impact at the Onset of the Younger Dryas?,” n.d., https://www.ldeo.columbia.edu/~broecker/Home.html.
As we saw: Kennett et al., “Nanodiamonds in the Younger Dryas Boundary Sediment Layer.”
A year later came the Nova program: Kurbatov et al., “Discovery of a Nanodiamond-Rich Layer in the Greenland Ice Sheet.”
Most evidence supporting [the YDIH] has been discredited: Tyrone L. Daulton, Nicholas Pinter, and Andrew C. Scott, “No Evidence of Nanodiamonds in Younger–Dryas Sediments to Support an Impact Event,” Proceedings of the National Academy of Sciences 107, no. 37 (September 14, 2010): 16043–47, https://doi.org/10.1073/pnas.1003904107.
In 2011 a group reported: H. Tian, D. Schryvers, and Ph Claeys, “Nanodiamonds Do Not Provide Unique Evidence for a Younger Dryas Impact,” Proceedings of the National Academy of Sciences 108, no. 1 (January 4, 2011): 40–44, https://doi.org/10.1073/pnas.1007695108.
These all peaked immediately: I. Israde-Alcantara et al., “Evidence from Central Mexico Supporting the Younger Dryas Extraterrestrial Impact Hypothesis,” Proceedings of the National Academy of Sciences 109, no. 13 (March 27, 2012): E738–47, https://doi.org/10.1073/pnas.1110614109.
In early 2014, another group confirmed :Leland C. Bement et al., “Quantifying the Distribution of Nanodiamonds in Pre-Younger Dryas to Recent Age Deposits along Bull Creek, Oklahoma Panhandle, USA,” Proceedings of the National Academy of Sciences 111, no. 5 (February 4, 2014): 1726–31, https://doi.org/10.1073/pnas.1309734111.
Then came a 2014 article: Charles R. Kinzie et al., “Nanodiamond-Rich Layer across Three Continents Consistent with Major Cosmic Impact at 12,800 Cal BP,” The Journal of Geology 122, no. 5 (September 2014): 475–506, https://doi.org/10.1086/677046.
The last word from opponents Tyrone L. Daulton et al., “Comprehensive Analysis of Nanodiamond Evidence Relating to the Younger Dryas Impact Hypothesis,” Journal of Quaternary Science 32, no. 1 (January 2017): 7–34, https://doi.org/10.1002/jqs.2892.
But Wolbach et al.: Wolbach, Wendy S., Joanne P. Ballard, Paul A. Mayewski, Andrei Kurbatov, Ted E. Bunch, Malcolm A. LeCompte, Victor Adedeji, Isabel Israde-Alcántara, Richard B. Firestone, and William C. Mahaney. “Extraordinary Biomass-Burning Episode and Impact Winter Triggered by the Younger Dryas Cosmic Impact 12,800 Years Ago: A Reply.” The Journal of Geology 128, no. 1 (2020): 95–107.

10. Wildfires

In 2018: Wendy S. Wolbach et al., “Extraordinary Biomass-Burning Episode and Impact Winter Triggered by the Younger Dryas Cosmic Impact ∼12,800 Years Ago. 1. Ice Cores and Glaciers,” The Journal of Geology 126, no. 2 (March 2018): 165–84, https://doi.org/10.1086/695703; Wendy S. Wolbach et al., “Extraordinary Biomass-Burning Episode and Impact Winter Triggered by the Younger Dryas Cosmic Impact ∼12,800 Years Ago. 2. Lake, Marine, and Terrestrial Sediments,” The Journal of Geology 126, no. 2 (March 2018): 185–205, https://doi.org/10.1086/695704.
Her conclusions about wildfires at the KTB were confirmed: Sean P. S. Gulick et al., “The First Day of the Cenozoic,” Proceedings of the National Academy of Sciences 116, no. 39 (September 24, 2019): 19342–51, https://doi.org/10.1073/pnas.1909479116.
One benefit of the "Big Data" capabilities: “Paleofire,” accessed November 13, 2018, https://paleofire.org/.

11. Hiawatha

Beneath Hiawatha Glacier: Kurt Kjær, “Abstracts,” Dansk Geologisk Forening, January 3, 2018, https://2dgf.dk/foreningen/33rd-nordic-geological-winter-meeting/ngwm-2018-abstracts/8-quaternary-geology/.
Then followed in November 2018: Kurt H. Kjær et al., “A Large Impact Crater beneath Hiawatha Glacier in Northwest Greenland,” Science Advances 4, no. 11 (November 1, 2018): eaar8173, https://doi.org/10.1126/sciadv.aar8173.
In drafts of the longer paper: Paul Voosen, “Massive Crater under Greenland’s Ice Points to Climate-Altering Impact in the Time of Humans,” Science | AAAS, 2018, https://www.sciencemag.org/news/2018/11/massive-crater-under-greenland-s-ice-points-climate-altering-impact-time-humans.
I think it is a possibility: “City-Size Impact Crater Found under Greenland Ice,” Science & Innovation, November 14, 2018, https://www.nationalgeographic.com/science/2018/11/impact-crater-found-under-hiawatha-glacier-greenland-ice/.
The sum of these tentative age constraints: Kjær et al., “A Large Impact Crater beneath Hiawatha Glacier in Northwest Greenland.”
Spurred by the finding: “Formation of Terrestrial Craters on Thick Ice Sheets,” AGU - AGU Fall Meeting 2018, accessed November 17, 2018, https://agu.confex.com/agu/fm18/meetingapp.cgi.
In early responses: Voosen, “Massive Crater under Greenland’s Ice Points to Climate-Altering Impact in the Time of Humans.”
Another made the same point: Carolyn Gramling, “A Massive Crater Hides beneath Greenland’s Ice,” Science News, November 15, 2018, https://www.sciencenews.org/article/impact-crater-greenland-asteroid-younger-dryas.
One veteran was “intrigued: Bartels, SPACE.com, “Scientists Spot Giant Crater Hidden under Greenland’s Ice.”
One of the discoverers had a different view: “Greenland Ice Sheet Hides Huge ‘Impact Crater,’” accessed November 18, 2018, http://blog.geogarage.com/2018/11/greenland-ice-sheet-hides-huge-impact.html.
Somebody's got to go drill in there: Voosen, “Massive Crater under Greenland’s Ice Points to Climate-Altering Impact in the Time of Humans.”
In 2018, a group from the Geological Survey of Canada: K.A. Jenner, D.C. Campbell, and D.J.W. Piper, “Along-Slope Variations in Sediment Lithofacies and Depositional Processes since the Last Glacial Maximum on the Northeast Baffin Margin, Canada,” Marine Geology 405 (November 2018): 92–107, https://doi.org/10.1016/j.margeo.2018.07.012.

12. Over Half the Earth's Surface

They studied a now dried-up ice-age lake: Gunther Kletetschka et al., “Cosmic-Impact Event in Lake Sediments from Central Europe Postdates the Laacher See Eruption and Marks Onset of the Younger Dryas,” The Journal of Geology, September 24, 2018, https://doi.org/10.1086/699869.
This result confirms an earlier study: Michael Baales et al., “Impact of the Late Glacial Eruption of the Laacher See Volcano, Central Rhineland, Germany,” Quaternary Research 58, no. 3 (2002): 273–288.
In mid-March 2019, a group of 16 authors published,: Mario Pino et al., “Sedimentary Record from Patagonia, Southern Chile Supports Cosmic-Impact Triggering of Biomass Burning, Climate Change, and Megafaunal Extinctions at 12.8 Ka,” Scientific Reports 9, no. 1 (March 2019): 4413, https://doi.org/10.1038/s41598-018-38089-y.
Broecker named this opposite response: Wallace S. Broecker, “Paleocean Circulation during the Last Deglaciation: A Bipolar Seesaw?,” Paleoceanography 13, no. 2 (April 1, 1998): 119–21, https://doi.org/10.1029/97PA03707.
In two articles: Bunch et al., “Very High-Temperature Impact Melt Products as Evidence for Cosmic Airbursts and Impacts 12,900 Years Ago”; Wittke et al., “Evidence for Deposition of 10 Million Tonnes of Impact Spherules across Four Continents 12,800 y Ago.”
Then in March 2020 came an article: Moore, Andrew M. T., James P. Kennett, William M. Napier, Ted E. Bunch, James C. Weaver, Malcolm LeCompte, A. Victor Adedeji, et al. 2020. “Evidence of Cosmic Impact at Abu Hureyra, Syria at the Younger Dryas Onset (~12.8 Ka): High-Temperature Melting at >2200 °C.” Scientific Reports 10 (1): 1–22. https://doi.org/10.1038/s41598-020-60867-w.
In October 2019: Moore, Christopher R., Mark J. Brooks, Albert C. Goodyear, Terry A. Ferguson, Angelina G. Perrotti, Siddhartha Mitra, Ashlyn M. Listecki, et al. 2019. “Sediment Cores from White Pond, South Carolina, Contain a Platinum Anomaly, Pyrogenic Carbon Peak, and Coprophilous Spore Decline at 12.8 Ka.” Scientific Reports 9 (1): 15121. https://doi.org/10.1038/s41598-019-51552-8.
In the Limpopo Province of South Africa: J. Francis Thackeray, Louis Scott, and P. Pieterse, “The Younger Dryas Interval at Wonderkrater (South Africa) in the Context of a Platinum Anomaly,” October 2, 2019, http://wiredspace.wits.ac.za/handle/10539/28129.

13. True Claims

He continued: Broecker, “An Extraterrestrial Impact at the Onset of the Younger Dryas?”
John Wasson and Mark Boslough noted: John T. Wasson and M.B.E. Boslough, “LARGE AERIAL BURSTS; AN IMPORTANT CLASS OF TERRESTRIAL ACCRETION-” (Lunar and Planetary Institute, Houston, 2000), 239–40.
In these cases, Boslough and colleagues concluded: Gordon R. Osinski et al., “The Dakhleh Glass: Product of an Impact Airburst or Cratering Event in the Western Desert of Egypt?,” Meteoritics & Planetary Science 43, no. 12 (December 2008): 2089–2107, https://doi.org/10.1111/j.1945-5100.2008.tb00663.x.
W. M. Napier modelled: Napier, W. M. 2019. “The Hazard from Fragmenting Comets.” Monthly Notices of the Royal Astronomical Society 488: 1822–27.

14. The Enigma of the Younger Dryas

In 1990, W. H. Berger reviewed the possible causes: Berger, “The Younger Dryas Cold Spell—a Quest for Causes.”
In a 1989 paper: W. S. Broecker, “Routing of Meltwater from the Laurentide Ice Sheet during the Younger Dryas Cold Episode,” Nature 341 (September 29, 1989), https://cloudfront.escholarship.org/dist/prd/content/qt9tk1g1r0/qt9tk1g1r0.pdf.
More recently, other scientists have shown: Julian B. Murton et al., “Identification of Younger Dryas Outburst Flood Path from Lake Agassiz to the Arctic Ocean,” Nature 464, no. 7289 (April 2010): 740–43, https://doi.org/10.1038/nature08954.
In a 2006 article in Science: Wallace S. Broecker, “Was the Younger Dryas Triggered by a Flood?,” Science 312, no. 5777 (May 26, 2006): 1146–48, https://doi.org/10.1126/science.1123253.
By 2006: Broecker.
Then, in that 2010 article: Wallace S. Broecker et al., “Putting the Younger Dryas Cold Event into Context,” Quaternary Science Reviews 29, no. 9–10 (May 2010): 1078–81, https://doi.org/10.1016/j.quascirev.2010.02.019.
A satisfactory explanation: Thomas JM Schopf, L. T. Silver, and P. H. Schultz, “Extinction of the Dinosaurs: A 1982 Understanding,” Geological Implications of Impacts of Large Asteroids and Comets on the Earth, 1982, 415–422.

15. Clovis

George McJunkin was born into slavery: Charles C. Mann, 1491: New Revelations of the Americas Before Columbus (Vintage Books, 2006), from which this section is largely drawn. I highly recommend his book.
William Henry Holmes: “William Henry Holmes,” in Wikipedia, July 23, 2018, https://en.wikipedia.org/w/index.php?title=William_Henry_Holmes&oldid=851625570.
He reported: Mann, 1491. The next three quotations are also from Mann.
He informed its experts: “The First Americans,” accessed January 22, 2019, http://scienceviews.com/indian/first_americans.html.
Ridgely had an ardent interest in fossils: “James Ridgley Whiteman, 1910 - 2003,” Plains Anthropologist 49, no. 189 (2004): 85–90.
He continued his fossil collecting: David J. Meltzer, First Peoples in a New World: Colonizing Ice Age America (University of California Press, 2009)., p. 239
According to Howard's telegraph: David J. Meltzer, The Great Paleolithic War: How Science Forged an Understanding of America’s Ice Age Past (University of Chicago Press, 2015).
In his speech,: Mann, 1491.
The early results showed: Mann.
At about the same time: Carole AS Mandryk, “The Ice-Free Corridor Revisited,” 1996.
From the glacial history of Canada: C. Vance Haynes, “Fluted Projectile Points: Their Age and Dispersion,” Science 145, no. 3639 (1964): 1408–13.
There is no doubt: Lorena Becerra-Valdivia et al., “Reassessing the Chronology of the Archaeological Site of Anzick,” Proceedings of the National Academy of Sciences 115, no. 27 (July 3, 2018): 7000–7003, https://doi.org/10.1073/pnas.1803624115.
In 2004, Bruce Bradley and Dennis Stanford: Bruce Bradley and Dennis Stanford, “The North Atlantic Ice-Edge Corridor: A Possible Palaeolithic Route to the New World,” World Archaeology 36, no. 4 (December 2004): 459–78, https://doi.org/10.1080/0043824042000303656.
Three opponents published: Lawrence Guy Straus, David J. Meltzer, and Ted Goebel, “Ice Age Atlantis? Exploring the Solutrean-Clovis ‘Connection,’” World Archaeology 37, no. 4 (December 2005): 507–32, https://doi.org/10.1080/00438240500395797.
Undaunted by the criticisms: Dennis J. Stanford and Bruce A. Bradley, Across Atlantic Ice: The Origin of America’s Clovis Culture (Univ of California Press, 2013).
One reviewer, archeologist John Shea, wrote: John J. Shea, “The Solutrean-Clovis Connection: Another Look,” Evolutionary Anthropology: Issues, News, and Reviews 21, no. 6 (November 2012): 293–95, https://doi.org/10.1002/evan.21321.
As a 2016 article concluded: Mikkel W. Pedersen et al., “Postglacial Viability and Colonization in North America’s Ice-Free Corridor,” Nature 537, no. 7618 (September 2016): 45–49, https://doi.org/10.1038/nature19085.
That Pre-Clovis people did have watercraft: J. M. Erlandson et al., “Paleoindian Seafaring, Maritime Technologies, and Coastal Foraging on California’s Channel Islands,” Science 331, no. 6021 (March 4, 2011): 1181–85, https://doi.org/10.1126/science.1201477.
The Channel Islands: Modern Chumash build a replica of the ancient boat, called a Tomol, from redwood trees that drift down the coast, fastening the cut planks together with animal sinews and sealing them with a combination of the pine pitch and asphaltum that occur naturally along the Channel coast from oil seeps. Periodically, they re-enact the voyage of their ancestors. https://www.nps.gov/chis/learn/historyculture/tomolcrossing.htm.
In 2018, a team dated the retreat: Alia J. Lesnek et al., “Deglaciation of the Pacific Coastal Corridor Directly Preceded the Human Colonization of the Americas,” Science Advances 4, no. 5 (May 2018): eaar5040, https://doi.org/10.1126/sciadv.aar5040.
Archeologists are going to have to figure out: Shea, “The Solutrean-Clovis Connection.”
It is seemingly hard for people: Peter Wood, “Failed Hypotheses in Academe and Beyond,” The Chronicle of Higher Education Blogs: Innovations (blog), March 25, 2011, https://www.chronicle.com/blogs/innovations/failed-hypotheses-in-academe-and-beyond/28990.
Then in 2015: Tom D. Dillehay et al., “Monte Verde: Seaweed, Food, Medicine, and the Peopling of South America,” Science 320, no. 5877 (May 9, 2008): 784–86, https://doi.org/10.1126/science.1156533.
The Monte Verde story proved: Tom D. Dillehay, “Monteverde PDF,” accessed October 12, 2018, http://www.uky.edu/Projects/MonteVerde/monteverde.pdf.
But Monte Verde was only the first of many: Michael R. Waters et al., “The Buttermilk Creek Complex and the Origins of Clovis at the Debra L. Friedkin Site, Texas,” Science 331, no. 6024 (March 25, 2011): 1599–1603, https://doi.org/10.1126/science.1201855.

16. The Fall of Clovis

As Nicole Waguespack notes: Nicole M. Waguespack, “Why We’re Still Arguing about the Pleistocene Occupation of the Americas,” Evolutionary Anthropology: Issues, News, and Reviews 16, no. 2 (April 24, 2007): 63–74, https://doi.org/10.1002/evan.20124.
A 2014 report showed: Waters, Michael R, and Thomas Wier Stafford. “The First Americans: A Review of the Evidence for the Late-Pleistocene Peopling of the Americas.” The First Americans, 2014, 21..
It described the finding: G. Sanchez et al., “Human (Clovis)-Gomphothere (Cuvieronius Sp.) Association 13,390 Calibrated YBP in Sonora, Mexico,” Proceedings of the National Academy of Sciences 111, no. 30 (July 29, 2014): 10972–77, https://doi.org/10.1073/pnas.1404546111.
The Greenland ice cores show: Steffensen et al., “High-Resolution Greenland Ice Core Data Show Abrupt Climate Change Happens in Few Years.”
In 2011: David G. Anderson et al., “Multiple Lines of Evidence for Possible Human Population Decline/Settlement Reorganization during the Early Younger Dryas,” Quaternary International 242, no. 2 (October 2011): 570–83, https://doi.org/10.1016/j.quaint.2011.04.020.

17. Great Monsters

As Charles Darwin began: Charles Darwin, The Voyage of the Beagle (P.F. Collier, 1909).
In 2003, Donald Grayson and David Meltzer wrote: Donald K. Grayson and David J. Meltzer, “A Requiem for North American Overkill,” Journal of Archaeological Science 30, no. 5 (May 2003): 585–93,ohttps://doi.org/10.1016/S0305-4403(02)00205-4.
But a year later: Stuart Fiedel and Gary Haynes, “A Premature Burial: Comments on Grayson and Meltzer’s ‘Requiem for Overkill,’” Journal of Archaeological Science 31, no. 1 (January 2004): 121–31, https://doi.org/10.1016/j.jas.2003.06.004.
Scientists have discovered only 14 "kill-sites,": Grayson and Meltzer, “A Requiem for North American Overkill.o
In Siberia and other parts of northern Eurasia: Yaroslav V. Kuzmin and Aleksei N. Tikhonov, “The Quaternary Extinctions in the Americas from a Siberian Perspective: Review of Paul S Martin. Twilight of the Mammoths: Ice Age Extinctions and the Rewilding of America. 2005. Berkeley and Los Angeles: University of California Press. ISBN: 0-520-23141-4;,” Radiocarbon 49, no. 1 (ed 2007): 181–84, https://doi.org/10.1017/S0033822200042004.
But among the hundreds of sites: Kuzmin and Tikhonov.
By one account: Paul L. Koch and Anthony D. Barnosky, “Late Quaternary Extinctions: State of the Debate,” Annual Review of Ecology, Evolution, and Systematics 37, no. 1 (December 2006): 215–50, https://doi.org/10.1146/annurev.ecolsys.34.011802.132415.
Humans precipitated extinction in many parts of the globe: Koch and Barnosky.
Haynes also told West: Firestone, West, and Warwick-Smith, The Cycle of Cosmic Catastrophes.

18. Paradigm Shifts

Professor Michael Jochim has noted: Michael Jochim, “Coping with the Younger Dryas in the Heart of Europe,” Hunter-Gatherer Behavior, May 23, 2016, https://doi.org/10.4324/9781315427133-12.
One team of scientists: J. Emili Aura et al., “Human Responses to Younger Dryas in the Ebro Valley and Mediterranean Watershed (Eastern Spain),” Quaternary International 242, no. 2 (October 2011): 348–59, https://doi.org/10.1016/j.quaint.2011.01.023.
As one review article noted: A. D. Barnosky, “Assessing the Causes of Late Pleistocene Extinctions on the Continents,” Science 306, no. 5693 (October 1, 2004): 70–75, https://doi.org/10.1126/science.1101476.
Reflecting this growing concern: National Research Council et al., Abrupt Climate Change: Inevitable Surprises (National Academies Press, 2002).
The best estimate of the cut-off: L. D. Keigwin et al., “Deglacial Floods in the Beaufort Sea Preceded Younger Dryas Cooling,” Nature Geoscience, July 9, 2018, https://doi.org/10.1038/s41561-018-0169-6.
For reference: S. O. Rasmussen et al., “A New Greenland Ice Core Chronology for the Last Glacial Termination,” Journal of Geophysical Research 111, no. D6 (2006), https://doi.org/10.1029/2005JD006079.
The Baltic Ice Lake began to collapse: Francesco Muschitiello et al., “Timing of the First Drainage of the Baltic Ice Lake Synchronous with the Onset of Greenland Stadial 1,” Boreas 45, no. 2 (April 2016): 322–34, https://doi.org/10.1111/bor.12155.

19. What If There Had Been No Younger Dryas?

This line of thinking calls to mind: Jared Diamond, Guns, Germs, and Steel: The Fates of Human Societies, Kindle (New York, London: W. W. Norton & Company, n.d.).
The first evidence of horse domestication: Davd W. Anthony, The Horse, the Wheel, and Language: How Bronze-Age Riders from the Eurasian Steppes Shaped the Modern World (Princeton and Oxford: Princeton University Press, 2007).
In The Red Pony: John Steinbeck, The Red Pony, Kindle (New York: Penguin, 1992).
One scholar believes: “Inca Success in Peruvian Andes ‘thanks to Llama Dung’ - BBC News,” accessed October 29, 2018, https://www.bbc.com/news/world-latin-america-13439093.
Later, the llama may have enabled the rise of the Incan Empire: “Llama,” in Wikipedia, September 17, 2018, https://en.wikipedia.org/w/index.php?title=Llama&oldid=860025038.
Its earliest depiction in prehistoric art: Anthony, The Horse, the Wheel, and Language: How Bronze-Age Riders from the Eurasian Steppes Shaped the Modern World.
Our words for horse and wagon: “Why It Took So Long to Invent the Wheel - Scientific American,” accessed October 29, 2018, https://www.scientificamerican.com/article/why-it-took-so-long-to-inv/.
By one estimate: Nathan Nunn and Nancy Qian, “The Potato’s Contribution to Population and Urbanization: Evidence from an Historical Experiment” (Cambridge, MA: National Bureau of Economic Research, July 2009), https://doi.org/10.3386/w15157.
Experts today agree: Greger Larson and Dorian Q. Fuller, “The Evolution of Animal Domestication,” Annual Review of Ecology, Evolution, and Systematics 45, no. 1 (November 23, 2014): 115–36, https://doi.org/10.1146/annurev-ecolsys-110512-135813.