Does the Tower of Babel Confirm Genealogical Gaps in Genesis 11?

Does the Tower of Babel Confirm Genealogical Gaps in Genesis 11?

A common assumption is that Genesis 5 and 11 contain complete, father-son genealogies without gaps and, therefore, one can rely on these genealogies to accurately calculate a date for creation and Noah’s flood. However, as we’ve previously presented,1 strong evidence shows that genealogy gaps exist. In this article, we will present additional evidence for genealogy gaps found in the Genesis 11:1–9 story of the Tower of Babel.
Bishop Ussher and other no-gap proponents typically date this event at Babel ~101 years after the flood around the time of the birth of Peleg (assuming Peleg is the fourth generation after Noah’s sons).2 However, the three reasons below suggest it is impossible for this incident to have occurred so soon after the flood.

Reason #1: Noah Was Never Apostate

Genesis 9:28 records that Noah lived 350 years after the flood. According to cultural norms, Noah would have been head of the clan who clustered in Babel ~101 years after the flood. The only way that Noah could have approved building a tower to heaven against the will of God is for him to have rejected God—yet this is not possible because the New Testament lauds Noah as a giant of the faith (Hebrews 11:7, 2 Peter 2:5). Moreover, if for any reason Noah could not serve as head of the clan, the job would have fallen to one of his sons; yet they, too, had witnessed the wrath of God and would surely be reluctant to undertake such a project against God’s will.

In summary, it is spiritually and culturally impossible to claim that the Tower of Babel occurred when Noah and his sons were still alive. It must have occurred much later when someone else was patriarch of the clan.

Reason #2: The Technology Is Too Complex to Develop in Only 101 Years

Genesis 11:3 states: “They [the men of Babel] said to each other, ‘Come, let’s make bricks and bake them thoroughly.’ They used brick instead of stone, and tar [chêmâr] for mortar.” This emphasizes that the Tower of Babel was not a simple mud brick structure like early Mesopotamian ziggurats; it was built of much stronger and more substantial fired brick. 3

Making fired bricks is a complex engineering endeavor. Clay soil must be mixed with a proper amount of sand and water (and any binders) and placed into molds. 4 A kiln must be built so the bricks can be brought to ~800°C (1450°F) for seven days or so to give them stone-like strength. 5 An anecdotal indication of the complexity is found in the autobiography of the brilliant Dr. Booker T. Washington, who set up a brickmaking operation in the 1880s:

I had always supposed that brickmaking was very simple, but I soon found out by bitter experience that it required special skill and knowledge, particularly in the burning of the bricks. 6

Washington’s first three kilns were failures and temporarily bankrupted him—yet this happened at a time when brickmaking was a mature art. By contrast, the people of Babel had to develop brickmaking by trial and error, and without any apparent prior knowledge.

The men of Babel used chêmâr—“tar,” or more accurately bitumen—for mortar. Bitumen deposits were common in the Tigris-Euphrates valley7 where Babel was located (Genesis 11:2), and archaeologists confirm that bitumen was commonly used as mortar in early Mesopotamia.8 But a central question is: how did the men of Babel know that they needed mortar and that bitumen would work well for that purpose? Noah did not use chêmâr to seal the ark (see Genesis 6:14); the men of Babel probably had to learn this by trial and error.

It is also obvious that a tower to heaven must be designed by experienced architects, and the construction overseen by experienced structural and construction engineers. In other words, the Tower of Babel required complex engineering on a number of levels. How could these descendants of Noah acquire this knowledge and experience in only three generations? God served as Noah’s chief engineer as he built the ark (Genesis 6:14–16); but the tower builders—working against God’s will—did not have the benefit of God’s direction to overcome the engineering obstacles. It seems inconceivable that all these technologies could be acquired by trial and error in a mere 101 years after the flood!

Reason #3: The Population Is Too Small

A tower to heaven would require a large number of laborers to collect clay, sand, and binders, mold lots of bricks, load and unload the kilns, transport the bricks to the building site, and to collect the bitumen and transport it to the site. Furthermore, the builders would require the support of an advanced society with agricultural surplus and division of labor efficient enough to provide food, shelter, clothing, and childcare for the community at large while diverting so many men to tower-building. Could Noah’s sons produce enough people in only 101 years?

The patriarchs in Genesis 11 averaged 31.4 years to the first child (excluding those who had children at an unusually old age). Genesis 10:2–3, 6–20, and 21–31 reveal that Shem, Ham, and Japheth had an average of 4.67 sons each, and their sons averaged five sons each; an equal number of daughters might be assumed.

Hence a biblically based population estimate can be made based on 10 children per couple and 30 years to the first child. On this basis, the world population would be a mere ~1,294 people (including only ~436 males 16 years of age or older and ~422 children under 16 years of age) about 101 years after the flood. It isn’t plausible that so few people might undertake all the engineering and labor-intensive tasks outlined—or that such a society could have sufficient division of labor to support it.

This conclusion is supported by a study of ancient cities that estimates a minimum of 10,000–100,000 people are required before “a systemic division of labor might take firm hold.”9 Babel would be far below these numbers ~101 years after the flood. Only in the sixth or seventh generation after Noah’s sons—almost 200 years after the flood—would the city have this many people. Yet even though there may have been enough people by this time, it still seems unlikely that the needed technology could be developed by then without God’s direction.

The Tower of Babel could not have occurred ~101 years after the flood in the fourth generation after Noah’s sons, as no-gap proponents believe, due to the following reasons:

  1. Noah would have had to fall into apostasy—but he did not.
  2. The engineering technology would have been too complex to develop by trial and error in such a short period of time.
  3. There would not have been nearly enough people to undertake such a project.

The tower had to occur many years later—meaning there must be gaps in the Genesis 11 genealogies, whether or not the tower occurred around the time of Peleg’s birth.

  1. Hugh Henry and Daniel J. Dyke, “From Noah to Abraham to Moses: Evidence of Genealogical Gaps in Mosaic Literature, Part 1,” Today’s New Reason to Believe (blog), Reasons to Believe, July 23, 2012,; Daniel J. Dyke and Hugh Henry, “Biblical Genealogies Revisited: Further Evidence of Gaps,” Today’s New Reason to Believe (blog), Reasons to Believe, November 18, 2013,
  2. This assumption is based on Genesis 10:25, which records: “because in his [Peleg’s] time the earth was divided.”
  3. “The History of Bricks: Mesopotamia,” Jane Street Clayworks, February 16, 2011,
  4. B. C. Punmia, Ashok Jain, and Arun Jain, Comprehensive Basic Civil Engineering (New Delhi, India: Laxmi Publications, 2003), 33.
  5. Hadar Jacobson, “What Is the Correct Firing Temperature?” Hadar’s Blog (blog), April 13, 2010,; “DIY—How to Make Clay Bricks in 6 Steps,” Bright Hub, September 22, 2010,
  6. Booker T. Washington, Up from Slavery (Garden City, NY: Doubleday, 1900) 151.
  7. Zayn Bilkadi, “Bitumen—A History,” Aramco World Magazine 36 (November/December 1984),
  8. K. Kris Hurst, “Bitumen—The Archaeology and History of Black Goo,”, last updated March 14, 2016,
  9. George Modelski, “Cities of the Ancient World: An Inventory (-3500 to -1200),” Evolutionary World Politics, July 10, 1997,