The Admixture Histories of Cabo Verde: New DNA Studies!

Cape Verde’s football team, a.k.a. Tubarões Azuis (The Blue Sharks), almost reached the semi-finals of the Africa Cup this year. Never mind being a “small” nation of around 1 million people (islands + diaspora). Cape Verdean team spirit, talent and guts are widely acclaimed! It must be in the genes 😉

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Ever since I got my first DNA test results in 2010 I have been researching my Cape Verdean roots from several angels. Of course everything starts with personal genealogy. But for deeper understanding I also take into account: population genetics, historical demography and cultural retention. In 2014 I created a separate website for this purpose: CVRAIZ: Specifying The African Ethnic Origins for Cape Verdeans. In 2015 (on this blog) I published my first survey findings based on Cape Verdean personal DNA test results. Furthermore I have always been applying a comparative analysis to see how Cape Verde fits in the broader picture of the Afro-Diaspora.¹

In the last couple of years several new peer reviewed studies have been published using a similar research approach. So that makes it very interesting to compare notes with my own research findings! I will mainly focus on the most recent study “The Admixture Histories of Cabo Verde” (Laurent et al., 2023) (original title prior to peer review). But I will also refer to a few other studies.

The Admixture Histories of Cabo Verde (Laurent et al., 2023)

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“Cabo Verdean Kriolu is the first creole language of the TAST, born from contacts between the Portuguese language and a variety of African languages. The archipelago thus represents a unique opportunity to investigate, jointly, genetic and linguistic admixture histories and their interactions since the mid-15th century.” (Laurent et al., p.4).

“We find that admixture from continental Europe and Africa occurred first early during the TAST history, concomitantly with the successive settlement of each Cabo Verdean island between the 15th and the early 17th centuries”. (Laurent et al., p.26).

“Finally, we find that recent European and African admixture in Cabo Verde occurred mainly […] in the 1800s“. (Laurent et al., p.27).

“our results highlight both the unity and diversity of the genetic peopling and admixture histories of Cabo Verde islands […].” (Laurent et al., p.27)

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Figure 1 (click to enlarge)Source: Korunes et al. (2022). This plot shows how there’s shared ancestry between all islands. Even when the degrees of kinship will naturally be greater on each separate island and also among certain subsets of islands. In particular the socalled NW cluster (a.k.a. Barlavento islands) and Boavista. Fogo is being mentioned as having the highest incidence of endogamy. While this study also confirms that Santiago is clearly the oldest population of the entire island group. Based purely on their DNA analysis but in fact in line with known history!

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Recent studies on Cape Verdean Genetics

• A genetic and linguistic analysis of the admixture histories of the islands of Cabo Verde (Laurent et al., 2023).
• Sex-biased admixture and assortative mating shape genetic variation and influence demographic inference in admixed Cabo Verdeans (Korunes et al., 2022).
• Rapid adaptation to malaria facilitated by admixture in the human population of Cabo Verde (Hamid et al., 2021).

My own research 

• 100 Cape Verdean AncestryDNA results (Fonte Felipe, 2018) 
• DNA matches reported for 50 Cape Verdeans on AncestryDNA (Fonte Felipe, 2018)
• 100 Cape Verdean 23andme results (Fonte Felipe, 2021)
• Ethnic group matches on 23andme for 50 Cape Verdeans (Fonte Felipe, 2022)

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I have been eagerly anticipating these most recent DNA studies on Cape Verdean genetics. And I am also very excited about the prospects for follow-up research. These new papers are firstmost a continuation of previous peer reviewed DNA studies about Cape Verde (see this link for an overview). In fact some outcomes repeat and reinforce my own earlier key findings (2011-2022).² Still there are a few intriguing novelties as well. Providing meaningful insight.

I truly appreciate all the efforts of the research teams behind these studies. But I do have to point out that I have mixed feelings about the accuracy of the historical framework. Especially as provided by Laurent et al. (2023). This study seems to have overlooked an essential aspect of Cape Verde’s historical demography. Because most likely already in the late 1600’s a majority of the Cape Verdean population (both black and mixed-race) was no longer enslaved (see this table). Cape Verde is indeed part of the Atlantic Afro-Diaspora. And especially in its early history (1460-1660) Cape Verde was greatly impacted by the TAST (Trans-Atlantic Slave Trade). But several singular aspects about the Cape Verdean experience do require very careful and context-dependent analysis!

1. Main outcomes
   • Genetic clustering of Cape Verdeans according to island origins.
   • Differentiation of African ancestry according to island origins.
     • Greater genetic affinity with Wolof samples among Barlavento islanders
     • Minor “Nigerian” and Central African lineage among Cape Verdeans
   • Various admixture pulses but all islands have substantial shared ancestry from the 1500’s.
2. Getting the historical context right
   • Most Cape Verdeans (80+% of population) have been free of slavery since at least 1731
   • Other points of critique.
3. Suggestions for future research
   • Sampling: apply criterium of 4 grandparents born on the same Cape Verdean island.
   • More granular analysis of non-Senegambian/Iberian origins: Sierra Leone, Sephardi Jewish, Goa etc..
   • New research agenda involving Cape Verdean Diaspora.

Single motherhood and genealogy: still stigmatizing?

This is the cover of a book my mother wrote in tribute to her mother. Dedicated to single motherhood, as both my mother and grandmother raised their children as unmarried women. The book was published ten years ago. I will always be super proud that my mother shared her story with readers across the world! From Cape Verde to Portugal and from Luxembourg all the way to Argentina!

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Single motherhood and its genealogical consequences are a very important topic. Not only when looking back at your own recent family history within the last 3 or 4 generations. But actually also when wanting to trace back further in time. Especially relevant for Afro-descended populations I would say. However in this blog post I am going to keep it short & sweet. Because my main intention is to wish my mother a Happy Mother’s Day 😀 Amor É Só de Mae!

I will focus mostly on my own personal background. Although again really I do think this is something which merits a much more elaborate approach. I am very curious to know if there have ever been any in-depth studies about this subject. If you have any suggestions, please let me know. Also feel free to share your own perspective/experiences in the comment section! 

Perhaps as a sign of the times genealogy is becoming ever more popular. However for some people researching their family history and deeper “roots” is more challenging than for others. Especially due to lacking or incomplete paper trails. Relying mostly on DNA testing instead. Which can be very helpful. But at times also quite shocking when revealing unknown family ties. Most notoriously when a non-paternity event is involved!

To answer the blogpost’s question: I feel immense pride and never-ending gratitude for having been raised by a strong single mother! In fact I hail from a long unbroken line of unmarried maternal ancestors, going back to at least my great-great-grandmother. But probably also beyond. I am aware of the social stigma which traditionally comes with having been born out of wedlock. But honestly this has never really bothered me in my personal life.

I understand that things might not be the same for everyone. But looking back, growing up in a single-parent household has been bliss (for the most part 😉 ). And in my adulthood I find it truly enriching to realize how much sacrifice my mother and my maternal ancestors before her had to endure in order to see their children survive & thrive. In fact my Cape Verdean grandmother not only raised her own 4 children but also 5 grand-children and 1 great-grandson!

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Contents of this blog post:

1. Fonte Felipe is just my nickname.
2. Maternal lineage or paternal lineage: which matters most? 

The Barbados Connection: beyond just South Carolina!

Rihanna is probably the most famous person from Barbados. Des’ree is another world-class singer of Bajan descent. However actually both singers have Guyanese mothers! The funny thing is that due to the intricate migration history of Barbadians there is still a good chance that their Guyanese mothers might have distant Barbadian ancestry as well. To be confirmed by genealogy but also to be corroborated by DNA testing!

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Due to multiple migrations (both forced and voluntary) the scope of ancestral connections within the Afro-Diaspora is very broad and at times unexpected! One country which stands out especially in this regard is Barbados. Of course whenever you have recent family ties to this easternmost Caribbean island you will already know about your Bajan descent. However for many people I imagine that discovering about distant Barbados ancestry will often come as a surprise. 

Learning about the various movements of people departing from Barbados and settling in several parts of the Americas will certainly be helpful then for better understanding. This blogpost is just meant as an introduction to this very intriguing topic. Highlighting some insightful resources and implications. The main take-away is that the Barbados Connection is extensive across many parts of the Afro-Diaspora. Not confined to South Carolina or even just North America. But in fact also to be found throughout the Caribbean, Central America and even South America. As they say: Bajans are everywhere!

Genetic Community on Ancestry: strong clue of (recent) Barbados Connection

Figure 1 (click to enlarge)

Source: Ancestry.com. This map shows one of the Genetic Communities on Ancestry. Labeled as “Lesser Antilles African Caribbeans”. But actually often pinpointing shared Barbadian ancestry. This tool is based on matching strength and the family trees of your DNA matches. The yellow dots highlight the extent and frequency of interrelated DNA matches. With a clear focus on Barbados, but otherwise extending from Panama to Suriname. And from the Virgin Islands to Trinidad.

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Genetic Group on 23andme: good clue of (recent) Barbados Connection

Figure 2 (click to enlarge)

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23andme results for a person from Suriname (see also this page). This Genetic Group feature (formerly known as recent ancestor location) is again based on matching strength. Often quite accurate although the implied ancestral scenarios are not always as straightforward as on Ancestry. So you have to be careful and not jump to conclusions. However this person from Suriname actually knows for a fact she has two great-grandparents from Barbados who migrated to Suriname as contract labourers in the late 1800’s.

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Confirmation of your Barbados connection by way of solid genealogical research is of course to be preferred. However DNA testing can also be very beneficial as shown above. Correct interpretation as always being a precondition. Whenever your Bajan link is relatively recent (~up till 1800’s) then this should normally result in a substantial genetic impact. Which will reflect in relatively close DNA matches with persons from Barbados; associated genetic communities/groups and at times also a distinctive African lineage or a distinctive African regional admixture level.¹ 

This last aspect brings me back to the main theme of my blog, Tracing African Roots. Albeit indirectly, by way of analyzing the African origins of Bajans. Especially to what extent the mix of their predominant African origins may deviate (relatively speaking) from other parts of the Afro-Diaspora. And how this may then translate into distinctive regional admixture levels and African DNA matching patterns for anyone with a substantial Barbados Connection. See also my upcoming survey results:

• African DNA matches reported for 30 West Indians on Ancestry (incl. 10 Barbadians, Trinidadians, Guyanese and Surinamese)

Contents of this blog post:

1. Extent of the Barbados Diaspora
   • Inter-Colonial Slave Trade (1600’s/1700’s)
   • Bajan migrations after Emancipation in 1834 
2.  Unique aspects of Barbadian demography
   • Early Creolization
   • White Barbadians
3. The Barbados connection: how does it impact your African lineage?
   • Major & distinctive provenance 
   • Main implications for different parts of the Afro-Diaspora 
4. Suggested Links

New Update on 23andme: Ethnic Group Matches within Africa! (part 2)

This is the second part of my blogseries which deals with the update last month on 23andme. Introducing no less than 25 ethno-linguistic groups from Africa to get matched with! In order to learn more about the ethnic origins of some of your African ancestors. In the first part of this series I already covered the question of how accurate these ethnic group matches might be. Follow link below for more details:

• New Update on 23andme: Ethnic Group Matches within Africa! (part 1)

In this post I will be focusing on what to expect. Basing myself mostly on the survey findings for 100 African Americans and 50 Cape Verdeans. But I will also post screenshots of updated results from other parts of the Afro-Diaspora.

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Figure 1 (click to enlarge)

These are the updated results of a Cape Verdean cousin of mine. It was already very useful how 23andme is able to pinpoint recent ancestry from Cape Verde. However with these new ethnic group matches also historically plausible origins from mainland Africa are confirmed for Cape Verdeans. Although to be sure there are many other ethnic groups from across Upper Guinea which also contributed to Cape Verde’s African Roots (see this website).

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Just to quickly repeat myself. Last month 23andme released its most recent update which could very well signal the start of a truly game-changing feature for zooming into ethno-linguistic African lineage¹. Of course this new feature on 23andme, based on matching strength, is not perfectly flawless. However despite a few shortcomings I am very excited about this update on 23andme! Because based on more than 50 updated results for Africans (see this overview) I am quite impressed with the accuracy of this tool. Also the results I have seen for 50 Cape Verdeans and 100 African Americans are actually in line with historical plausibility.

This update has already been fully rolled out.² But still the odds of obtaining even only one of the 25 ethno-linguistic groups are rather low for most people. Depending also on your background. It seems for African Americans there’s only about a 20% chance. For many people 23andme is simply not able to detect a sufficient level of matching strength. Which is inevitable given the limitations of 23andme’s current African reference database. Understandably this may come as a big disappointement. However don’t despair because this update is a work in progress and upcoming updates will eventually reach more people! Glass half full mentality also for 2022 😉

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Figure 2 (click to enlarge)

Take note that the updated results on the right only feature one ethnic group match. Despite this African American woman being over 80% African and regionally speaking from atleast 4 major areas in West & Central Africa. Of course this finding in itself is already incredibly valuable. However this possibly Fula and/or Wolof lineage most likely covers less than 5% of her total ancestry. While for her primary region “Nigerian” not a single ethnic group has appeared yet. In fact, although not being detected she might still also have additional Mandinka ancestors. To be grouped under “Senegambian & Guinean”. Follow-up research is still needed if you want to uncover your entire African lineage!   

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In the remaining part of this blog post I will discuss the following:

1. Survey findings for 100 African Americans
   • “Igbo”, “Kongo & Mbundu” and “Fula & Wolof” most frequent
2. Survey findings for 50 Cape Verdeans
   • “Fula & Wolof” and “Mandinka” most frequent
3. Updated results from other parts of the Afro-Diaspora 
   • Atlantic Afro-descendants (Brazil, Dominican Republic, Jamaica, Haiti etc.)
   • Indian Oceanic Afro-descendants (Mauritius/Réunion, Seychelles, South African Coloured, UAE)
4. Considerations
   • Recap previous disclaimers
   • Some ethnic group matches appear more frequently than others
   • Each regional admixture category potentially includes ancestors from various ethnic groups

Are African Americans really mostly “Nigerian”?

Last year 23andme’s research team published a major landmark study titled “Genetic Consequences of the Transatlantic Slave Trade in the Americas“. Arguably the largest DNA study to examine African ancestry in the Americas! Covering a wide span of the Afro-Diaspora, incl. also several thousands of African Americans. Highly interesting therefore. The research approach of this study consists of combining genetic data obtained from 23andme customers with Trans-Atlantic Slave Trade patterns. Which is practically the same approach I have been using ever since I started my AncestryDNA survey in 2013. This study by 23andme is even including Cape Verdean samples as a control group! Which is something I have done as well in all my research sofar.¹ Since I have recently finished my survey findings based on 23andme results (2018/2019 version) it should be useful to compare notes.

23andme’s 2020 study

• Genetic Consequences of the Transatlantic Slave Trade in the Americas (Micheletti et al., 2020)
• Supplemental Data Micheletti et al, 2020
• Table S7. Mean Ancestry Composition for the Research Cohort (main source for comparison) 

My own survey findings based on 23andme and AncestryDNA results

• Afro-Diaspora AncestryDNA results: A Comparison (Fonte Felipe, 2016)
• Update: Afro-Diasporan AncestryDNA Survey (part 1) & part 2) (Fonte Felipe, 2018)
• 23andme’s African breakdown put to the test: Afro Diaspora edition! (Fonte Felipe, 2021)

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Table 1 (click to enlarge)

This overview is showing the scaled African breakdown for the combined USA sample group (n=5785) featured in Micheletti et al. (2020). As well as for my own African American survey group (n=200). Despite smaller sample size actually very similar outcomes. Providing mutual corroboration. As can be seen “Nigerian” was clearly the most significant region. Going by group averages around 35%. Usually “Nigerian” is appearing as primary African category (162/200=81% in my survey). But even so “Nigerian” is still far from being predominant (>50%). Especially “Ghanaian, Liberian & Sierra Leonean” is also showing up as a substantial component. Furthermore regional scores indicative of Senegambian and Central African DNA are still considerable and nearly at 10%, on average. Making for an overall varied and rather balanced African breakdown. Do notice as well that around 20% of the African breakdown is falling in one of the “Broadly” categories!

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In this blogpost I will compare my own research findings (based on regional admixture) with 23andme’s study from 2020. In fact much of the data contained in 23andme’s study (based on the 2018 version of Ancestry Composition) is consistent with my own. As demonstrated above in Table 1. Which features the African breakdown for African Americans on 23andme (scaled to 100%).² Despite smaller sample size on my part actually very similar outcomes. Providing mutual corroboration. The study’s main findings of lower Senegambian and higher Nigerian ancestry than expected for African Americans are in line with what I had already established in my 2015 survey. Based on AncestryDNA test results for 350 African Americans. As well as more recently in my 23andme survey. See also:

• 350 African American AncestryDNA results (2015)
• 200 African American 23andme results (2018/2019 version)

Within the remaining part of this blog post I will discuss the following:

1. Why do so many African Americans have Nigerian ancestry?
   • Ancestral implications of “Nigerian” go beyond modern-day borders
   • Domestic Slave Trade from mostly Virginia spreading Bight of Biafra lineage
   • Lower Senegambian than expected because of less reproduction?
   • Substructure according to state origins
2. African breakdown for other parts of the Afro-Diaspora 
   • Mostly in agreement with historical expectations
   • Overlap & differences with my own survey findings
   • Regional diversity and substructure
   • Confirmation of Upper Guinean Founding Effect?
3. Discordances & limitations of 23andme’s study
   • Afro-descended samples taken from migrants underrepresent wider variation in countries of origin
   • Central African IBD disproportionately high when contrasted with regional admixture from Central Africa 
   • Sex-biased admixture: multiple & context-dependent historical narratives! 
4. Exciting future prospects:  personalized 23andme results featuring African IBD specified according to ethnic groups

23andme’s African breakdown put to the test: Afro Diaspora edition!

In the last couple of years 23andme has implemented several updates. Often beneficial for Tracing African Roots! Starting with the introduction of a new African regional framework in 2018. Finally providing a meaningful breakdown of West & Central African ancestry! Soon afterwards I started a survey of 23andme results among Africans as well as African Americans and other Afro-descended nationalities.¹ Similar to my previous Ancestry surveys my main research goal has always been to establish how much these results on an aggregated group level can already (despite limitations of sample size and other shortcomings) be correlated with whatever is known about the documented regional African roots for each nationality. As well as to improve correct interpretation of personal results.

Two years ago in February 2019 I published the first part of my examination of 23andme’s African breakdown. Which was based on my surveyfindings for 173 African 23andme testers from 31 countries (see this blog post). My 23andme survey has been ongoing till 23andme’s update in October 2019.² Because of other projects I have not been able to process my entire data-set earlier. But in this blog post I will at last present my main 23andme survey findings based on 889 results from 28 different countries across the Afro-Diaspora! Actually I have already analyzed these results in greater detail (incl. screenshots of individual results) on these pages:

• African American 23andme results
• Brazilian 23andme results
• Cape Verdean 23andme results
• Dominican 23andme results
• Haitian 23andme results
• Hispanic 23andme results
• Jamaican 23andme results
• Puerto Rican 23andme results
• West Indian 23andme results

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Figure 1 (click to enlarge)

A small selection of 23andme results from across the Afro-Diaspora.  Most of the outcomes are roughly corresponding with documented African roots  for each of my survey groups. Unrealistic expectations about “100% accuracy” as well as counter-productive obsessing about regional labeling should be avoided. Instead focus on what ever informational value you can obtain despite imperfections. Take notice as well how the additional Recent Ancestor Locations are on point!

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To summarize: I do indeed believe that 23andme’s African breakdown has passed the test! Although obviously there are several shortcomings to take into account. Based on both my African and Afro-Diasporan surveyfindings I find it quite impressive though that 23andme is often able to describe a person’s African origins in a meaningful regional framework. Which will usually quite closely correspond with either known genealogy or historical plausibility. The additional non-African scores and Recent Ancestral Locations actually reinforcing the robustness of 23andme’s predictions. In the remaining part of this blog post I will discuss the following:

1. African Breakdown
   • Main outcomes
     • Upper Guinean Founding Effect for Hispanic Americans
     • Virginia’s African roots most impactful on African American overall genepool?
     • Meaningful differentiation between Anglo-Caribbeans, Dutch Caribbeans and Garifuna
   • Frequency of primary African regions
   • Historical plausibility
2. Substructure
   • African Americans, Brazilians, Cape Verdeans, Haitians, Hispanic Americans, West Indians
3. Continental Breakdown
   • Southeast Asian admixture indicative of Madagascar connection
4. Recent Ancestor Locations:
   • Pinpointing African lineage
   • Cross-Diaspora connections
5. Screenshots 
   • Distinctive results across the Diaspora
   • Similar results across the Diaspora
   • Underrepresented parts of the Afro-Diaspora
   • Hispanic results reflecting Upper Guinean Founding Effect
   • Partially Cape Verdean results

ROOTSTECH 25–27 FEBRUARY 2021: Don’t Miss It!

For those who are not aware: ROOTSTECH Connect is the world’s largest family-history technology conference. And this year it will be a completely FREE and VIRTUAL experience! Hundreds of amazing sessions will be available online during and also after RootsTech Connect has ended on February 27th! Many of those sessions will offer precious insight for Africans and Afro-descendants in their quest to Trace African Roots! All it takes to attend is a free online registration. Right now more than 315,000 participants from more than 200 countries and territories worldwide have already registered! For more details:

• ROOTSTECH CONNECT 2021 
• Classes for Africans by Africans (series)
• Discovering African Ancestry through DNA (series)
• Ethnic Filters and DNA Matches: The Way Forward to Finding Your Lineage! (my own presentation!)

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I am very honoured, grateful and excited to also be part of this tremendous event! Because I will be giving an presentation as well! I will be demonstrating my scanning and filtering method to zoom into African matches or any other type of lineage you are interested in researching. I originally devised this technique in 2017. And I have been using it ever since to conduct my ongoing African DNA matches surveys. After registering for ROOTSTECH you should be able to find my class listed in the various search menus. But you can also just directly see it by following the link provided above.

If you are having trouble finding your African DNA cousins this can hopefully offer you a great opportunity to systematically look for your African DNA matches! During the event there will be an occasion to ask any questions by way of a chatroom. But of course you can also always reach me here on my blog if anything needs clarification or just to leave a comment. See also:

• How to find those elusive African DNA matches on Ancestry 
• African DNA Matching Patterns

In the remaining part of this blog post I will show a few slides for a sneak preview 😉 Furthermore I will also provide all materials/links mentioned during my presentation. For those intending to watch my presentation: Thank you for your attention! I will be rooting for you that the ethnic filtering method I have discussed will be beneficial for you as well! 

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Let’s get this cocktail party started! 😉

Slave Voyages: not only Trans-Atlantic but also Intra-American!

This blogpost is mainly intended to announce a major overhaul for one of the most important sections on my blog:

• Regional Origins of the Afro-Diaspora according to Documented Slave Trade Patterns

The page referred to above is now featuring new screenshots taken from the invaluable Trans-Atlantic Slave Trade Database as well as the additional Intra-American Slave Trade Database. Reflecting the current state of knowledge. I am convinced that the data contained on that page can be very educational and useful for anyone wanting to learn more about their African roots. Just as long as you keep in mind inherent limitations and inform yourself about the relevant context. This kind of aggregated information is probably most useful on a population level.¹ But also for your personal quest it can provide you with a very valuable starting point! In particular in order to judge the historical plausibility of any DNA test results you may have received. Not only regional admixture or haplogroups but also African DNA matches. And even DNA matches from across the Afro-Diaspora!²

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Despite its limitations the Trans-Atlantic Slave Trade Database (TAST) is simply the most comprehensive and up-to-date resource available when wanting to look into Trans-Atlantic Slave Trade patterns. The website was updated in 2019. It now includes information about more than 36,000 Trans-Atlantic slave voyages! See also this recommendation by Henry Louis Gates.

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““If there were a Pulitzer Prize given for historical databases, the Transatlantic Slave Trade Database would win it, hands down,” says Gates, Alphonse Fletcher University Professor at Harvard.” (source)

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I myself have often relied heavily on the Trans-Atlantic Slave Trade Database as some sort of baseline. To establish historical plausibility within my ongoing research efforts on how personal DNA test results of Afro-Diasporans may already be in alignment with historical expectations. See also:

• AncestryDNA Surveys (2013-2018)
  • Documented African origins confirmed on group level? (2016) (scroll down to section 4)
  • Afro-Diasporan AncestryDNA Survey (part 1) (2018)
• 23andme surveys (2019-ongoing)
• African DNA Matching Patterns (2017-ongoing)

It can be very tempting to correlate slave trade records with population genetics or assumed ethnic/regional origins of Afro-descended populations. Given the absence of more straightforward information. But such an approach can hold many pitfalls. Even if the Slave Voyages database is deemed to provide nearly fully coverage for any particular country. This is because you cannot just simply assume that there will be a direct extrapolation from the data at hand. Reality is too complex regrettably. Several factors need to be taken into account. Mainly to do with incomplete knowledge about the demographic evolution of enslaved Africans and their descendants. See the updated section for more detailed discussion. This aspect might be most pertinent:

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• Intra-American Slave Trade, Domestic overland Slave Trade and Post Slavery migrations have resulted in great deal of additional intermingling and diversification of African lineage. This is especially true for the USA and Brazil because of their continental size. But in fact also for most parts of the Caribbean and Latin America.

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Table 1 (click to enlarge)

Based on these estimates (taken from O’Malley, 2009),  Intra-American Slave Trade for North America was around 15%. The actual shares per state do show important variation. For Virginia and South Carolina this share of slave trade by way of the Caribbean is  quite minor: around 10%. However for other states it is more substantial. Do keep in mind though that Domestic (overland) Slave Trade is not taken into account. While actually going by sheer numbers this type of Slave Trade was most significant for the USA. An estimated 1 million enslaved African Americans (often with Virginia background) are known to have been victimized by the so-called Second Middle Passage (see this link).

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Obviously there will be other factors as well that could explain genetic results being disproportionate to what you might expect based on slave trade data. Substructure within any given Afro-descended population also being highly relevant. This is something which I have blogged about several times already and also in upcoming blog posts I will return to this important topic. Within the remaining part of this current blog post I will discuss the following:

1. Trans-Atlantic Slave Trade Database
   • Newly added Portuguese & Spanish Slave Voyages (1500’s) corroborate Upper Guinean founding effect for many Hispanic Americans
2. Intra-American Slave Trade Database
   • Disclaimers
   • Intra-American Slave Trade Patterns for the USA
3. Final Passages: The Intercolonial Slave Trade of British America, 1619-1807 (G. E. O’Malley, 2014)
   • Excellent research. I will feature some key insights and overviews from this highly recommended book.

The Mozambique connection on Ancestry & MyHeritage

Mozambique is a somewhat overlooked country of origin for many Afro-descendants. To be sure the Trans-Atlantic Slave Trade with Southeast Africa was relatively smaller in scope than with either West or Central Africa. Still according to most recent estimates it involved almost half a million people (see this overview from the TAST database). Especially for Brazilians, Haitians and Cubans Mozambican lineage might be considerable in some cases. Plus also the Indian Ocean Slave trade is to be taken into account. Which most likely resulted in a dispersion of a similar number of Mozambicans (see this overview, taken from this paper). Especially into South Africa and the Indian Ocean Islands: such as Mauritius, Réunion and Madagascar. But also to the Middle East and into South Asia and beyond even. For more details:

• Southeast African Trans-Atlantic Slave Trade
• The African Diaspora in the Indian Ocean World

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Map 1 (click to enlarge

I found 12 most likely African matches for a person who is himself 1/2 Mozambican and 1/2 Portuguese. Most of these matches actually were likewise of mixed background. With the majority being from South Africa (6x). But also tellingly one single close match from presumably Pemba, Mozambique! MyHeritage provides a very useful filtering tool which allowed me to zoom into shared East African DNA segments among this person’s DNA matches.

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Then again some people might also have Mozambican ancestry due to recent migrations. In the last couple of months I have been given access to DNA results which reveal an already confirmed Mozambique connection for two people of mixed background. With very fascinating outcomes! As well as useful implications for other people wanting to learn more about their own possibly Mozambican lineage.

The first person is living in the Netherlands (like me). Both of his parents were born in Mozambique. But going back two generations his father’s grandparents are all of Portuguese descent. While his mother’s family has been living in Mozambique for as long as can be traced back. But her family tree does contain at least two persons who were born in India and migrated to Mozambique as well. When it was still under Portuguese rule. All in all a very fascinating tale of migration across several continents! This person tested with MyHeritage and he has been featured in a Dutch documentary series called “Identity”. I was actually honoured to also contribute to this documentary which was shot in my birth place Rotterdam. The actual day of filming being the 5th of July which happens to be Cape Verde’s Day of Independence! Highly symbolic for me therefore 😉 ¹ See also:

• IDENTITY by Stacii Samidin
• ROOTS.NL (S1E3): True Colours: Dutch Race Relations

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Figure 1 (click to enlarge)

These are the recently updated AncestryDNA results of a person whose father is from Mozambique. His Southeast African DNA is clearly indicated by his main regions, incl. also “Eastern Bantu”! Another intriguing aspect is that this person actually also has a Cape Verdean connection by way of São Tomé & Principe. This is revealed by a very distinctive score of 6% “Senegal”. Probably also to be combined with the “Portugal” & “Spain” scores. Highlighting that regional admixture DOES matter!

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The other person is a DNA cousin of mine on Ancestry whose mother was born in São Tomé & Principe while his father is from Mozambique. I am related to him by way of a mutual Cape Verdean relative who migrated to São Tomé & Principe as a contract labourer during the first half of the 1900’s. São Tomé & Principe is a former Portuguese colony just like Cape Verde and Mozambique. But nowadays it is an independent island state located nearby Gabon in the Gulf of Guinea. Just like Angolans and Mozambicans many Cape Verdeans ended up settling in São Tomé & Principe during the Portuguese colonial time. Notoriously being employed under very harsh circumstances on the cocoa plantations of São Tomé & Principe. It therefore still has a sizeable community of Cape Verdean descendants. Their continued longing for their motherland has been made world famous by the song “Sodad” by Cesaria Evora (see this video clip).

This blog post will describe the DNA results of both persons. Seeking to demonstrate in particular how correlating regional admixture analysis with DNA matches can be rewarding and mutually reinforcing in many cases. In addition I will also discuss my experience with MyHeritage. As I have myself not tested with this company. And so this was the first time I had the chance to get acquainted with several of its features. Allowing me to also make some cross-comparisons with Ancestry.

• Mozambican Connection on MyHeritage
• Mozambican Connection on Ancestry
• Comparing Ancestry with MyHeritage
  1. MyHeritage is distorting Central & Southeast African DNA
  2. Ancestry offers greater potential to find African matches
  3. MyHeritage provides more advanced filtering tools

Ancestry’s 2019 Update: Back on Track Again?

Map showing all the regions available on Ancestry after its 2019 update. For Trans Atlantic Afro-descendants the most impactful changes seem to be that: “Nigeria” has been brought back to life again! But “Ghana” has been derailed. “Mali” is no longer overpowering “Senegal”, but it does include both Sierra Leone and Liberia now! See this link for a complete list of regions and genetic communities. Photo credits for top picture showing a train passing by a railway station in Ghana.

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Starting in October 2019 Ancestry has been rolling out a new update of their Ethnicity Estimates. As I have said before your DNA results are only as good as the next update. So it is best not to get too attached to them 😉 Given scientific advancements and a greater number of relevant reference samples one always hopes that a greater degree of accuracy may be obtained. But naturally no guarantees are given that this will indeed be the case. After all Ancestry’s update in 2018 arguably was a downgrade rather than providing any meaningful improvement! At least when it comes to the African breakdown. In regards to the European, Asian and Amerindian breakdown Ancestry seems to have made steady progress on most fronts. Continued also with this 2019 update.

From my experience the best indication of predictive accuracy is obtained by looking at how Africans themselves are being described when tested by Ancestry. Which is why I have performed a comprehensive survey among 136 African Ancestry testers from all over the continent to establish a more solid basis for judgement. In addition I have also looked into a representative array of 55 updated results from across the Afro-Diaspora. These findings will be described in greater detail further below. The outcomes are mostly positive for Africans themselves but more ambivalent for Afro-descendants. Probably because Ancestry’s algorithm is less adequate when describing the mixed and therefore more complex African lineage of the Afro-Diaspora. My overall verdict about this 2019 update: a step in the right direction but no substantial improvements for the most part. At least not when compared with the original African breakdown from the 2013-2018 version.

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Table 1 (click to enlarge)

Based on the updated results for 121 African AncestryDNA testers from 30 countries, across the continent. Take notice that the predictive accuracy in most cases is quite solid. Although in a few cases it is still clearly in need of improvement. This goes especially for “Ghana” and “Eastern Bantu”. Follow this link for my spreadsheet containing all the individual results.

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Due to wild fluctuations in just two years many people might experience update fatigue. Some people will even be tempted to bash their DNA test results and admixture analysis in particular. But an overtly dismissive stance will be self-defeating and deprive you of informational value yet to be gained! As I have always argued that regional admixture DOES matter and Ancestry’s Ethnicity Estimates are of course NOT randomly determined.¹ Ancestry’s predictions may not be 100% accurate but still in most cases they are reasonably well-aligned with the known backgrounds of my African survey participants. As can be verified from the overview above.

For those perplexed by all the changes do at least make an attempt to inform your self properly. Given how wrong Ancestry got it in 2018 (see this blog series) it is only natural that some grave flaws had to be rectified. Regrettably it seems in some aspects an over-correction did take place. Still depending on your background this update certainly also can be beneficial. Furthermore when considering your African breakdown in a macro-regional framework the changes have actually not been that drastic. And many things more or less remained consistent as I will discuss in section 3 of this blog post.

It has always been my belief that regional estimates require correct interpretation. And each updated version as well as each separate DNA testing company should therefore be judged on its own terms. Then again these admixture results can only take you that far. My advise is to also look into your African DNA matches, as well as historical plausibility and just plain genetic genealogy for greater combined insight. See also these links:

• Ethnicity Update FAQ (Ancestry)
• How to deal with updated DNA test results 
• How to find those elusive African DNA matches on Ancestry
• African DNA Matches Service

For those seeking deeper understanding of Ancestry’s 2019 update this blog post will attempt to take things further by having a closer look at:

1. African breakdown for Africans before and after the 2019 update
2. Ancestry’s Reference Panel & Algorithm
3. African breakdown for Afro-descendants before and after the 2019 update
4. Getting back on track again
5. Screenshots of African updated results
6. Poll on whether this update has been an improvement or not, please vote!