An outreach talk I gave on human evolution discussing whether human evolution is still occurring.

1. Hey, you.

2. Yeah, you.

3. Hands up if you agree:
Humans are no longer evolving.

4. Hands up if you agree:
Humans are no longer evolving.
(I see you there in the back)

5. If so, you’re in good company.

6. Stephen J. Gould

7. Ernst Mayr

9. Are humans still evolving?
Steven Hamblin
University of New South Wales
School of Biotechnology and Biomolecular Sciences

11. YES.

12. Change in gene frequencies
in a population
from generation to generation

13. mutation
NATURAL selection
genetic drift
gene flow (migration)

14. mutation
NATURAL selection
genetic drift
gene flow (migration)

15. Past

16. Present

17. Future

18. Past

19. Past Present future

20. Past Present future

21. Past Present future

22. Past Present future

23. Past Present future
Distribution of LP in the ‘Old World’
Gerbault P et al. Phil. Trans. R. Soc. B 2011;366:863-877

24. Past Present future

25. Past Present future
Culture
accelerates
evolution

26. Past Present future
The incredible
SHRINKING BRAIN

27. Past Present future
20,000 years ago Present day
1500 cc 1350 cc

28. Microcephaly

29. Tajima_s D, which is a summary statistic for nants between D and non-D chromosomes as We genotyped the diagnostic G37995C SNP in
the frequency spectrum of alleles, is –2.3 for evidenced by recombination tracts (table S2). this panel to infer the frequency of haplogroup D
Past Present future
haplogroup D (whereas it is –1.2 for the
non-D chromosomes). This strongly negative
The remaining 121 copies of haplogroup D
chromosomes show no evidence of recom-
chromosomes (Fig. 3). Geographic variation
was observed, with sub-Saharan populations
Tajima_s D indicates a starlike genealogy for bination. By comparison, the non-D chromo- generally having lower frequencies than others.
haplogroup D chromosomes (47). Thus, both somes do not display any significant LD across The statistic for genetic differentiation, FST, is
summary statistics contrast sharply between D the region. 0.48 between sub-Saharans and others, which
and non-D chromosomes and are consistent To probe the extent of LD beyond the indicates strong differentiation (48) and is sig-
with the recent age and rapid expansion of 29-kb core region, we sequenced the Coriell nificantly higher than the genome average of
Downloaded from www.sciencemag.org on March 6, 2013
haplogroup D. We note that these calculations panel for two segments of about 3 kb each, 0.12 (P G 0.03 based on previously established
do not provide a statistically stringent test of situated at the beginning and end of the gene genomewide FST distribution) (49). Such pop-
positive selection, because they are done on separated from each other by about 235 kb. In ulation differentiation may reflect a Eurasian
MPCH1
subsets of the genealogy. Nevertheless, they do these flanking regions, there is clear evidence origin of haplogroup D, local adaptation, and/or
Evans et al. (2005)
Fig. 3. Global frequencies of Microcephalin haplogroup D chromosomes 62.5%); 24, Brahui (Pakistan, 25, 78%); 25, Kalash (Pakistan, 24, 62.5%); 26,
(defined as having the derived C allele at the G37995C diagnostic SNP) in a Sindhi (Pakistan, 25, 78%); 27, Hezhen (China, 9, 77.8%); 28, Mongola
panel of 1184 individuals. For each population, the country of origin, (China, 10, 100%); 29, Daur (China, 10, 85%); 30, Orogen (China, 10,
number of individuals sampled, and frequency of haplogroup D chro- 100%); 31, Miaozu (China, 9, 77.8%); 32, Yizu (China, 10, 85%); 33, Tujia
mosomes are given (in parentheses) as follows: 1, Southeastern and (China, 10, 75%); 34, Han (China, 41, 82.9%); 35, Xibo (China, 9, 83.3%);
Southwestern Bantu (South Africa, 8, 31.3%); 2, San (Namibia, 7, 7.1%); 36, Uygur (China, 10, 90%); 37, Dai (China, 9, 55.6%); 38, Lahu (China,
3, Mbuti Pygmy (Democratic Republic of Congo, 15, 3.3%); 4, Masai 10, 85%); 39, She (China, 9, 88.9%); 40, Naxi (China, 10, 95%); 41, Tu
(Tanzania, 27, 29.6%); 5, Sandawe (Tanzania, 32, 39.1%); 6, Burunge (Tan- (China, 10, 75%); 42, Cambodian (Cambodia, 11, 72.7%); 43, Japanese

30. Signals of
SELECTION Oleksyk et al. (2010)
Phil. Trans. R. Soc. B (2010)
Table 2. Candidate genes, the tests used to identify selection and GWSSs that found them. (The candidate genes with any evidence of selection found by genom
not applicable.)
chromo- found by scan (same
some gene location author discovered by test(s) population(s) locus)
1 FY 1q21 –q22 Hamblin & Di frequency spectrum, Fay and Wu’s H, FST Africans
Rienzo (2000) population
differentiation
1 AGT 1q42 –q43 Nakajima et al. unusual LD tight LD Africans
(2004)
1 ASPM 1q31 Mekel-Bobrov et al. comparative methods Ka/Ks World
(2005)
2 LCT 2q21 Bersaglieri et al. unusual LD iHs, EHH Europeans, Frazer et al. (2007);
(2004) World Nielsen et al. (2005);
Voight et al. (2006)
2 CAPN10 2q37.3 Fullerton et al. population differences FST Africans versus
(2002) non-African
3 CCR5 3p21.31 Stephens et al. population differences FST and low Europeans Oleksyk et al. (2008)
(1998) heterozygosity

31. Present

32. Past Present future

33. Past Present future

34. Past Present future

35. Past Present future

36. Past Present future
Plasmodium falciparum
Malaria

37. Past Present future
660,000 deaths
in 2010

38. Hemoglobin A/S

39. Past Present future
sickle cell
anemia

40. Past Present future
Aidoo et al. (2002)

41. Past Present future
se lec tion
al anc ing
B

42. Past Present future

43. Past Present future
That’s 52 million.
http://edition.cnn.com/2012/11/14/opinion/china-challenges-one-child-brooks

44. Past Present future
Asia’s missing women
Figure 1. Childhood sex ratios in eight countries responsible for the largest number of
missing women and girls, compared with the childhood sex ratio for the rest of the world
(dashed line)
Note: Data from CIA World Factbook.
Some diseases alter the probability of a woman giving birth to a boy or girl.
Infection with the protozoan parasite Toxoplasma gondii, for example, can cause sex ratios
Brooks (2012)

45. Past Present future
TIO
SeX RA

46. Past Present future
Infanticide
Reproductive skew
Male conflict

47. Past Present future

48. Past Present future

49. Past Present future

50. Future

51. Is human evolution
finished?

52. Past Present future

53. Past Present future

54. Past Present future

55. Past Present future
influenza
norovirus
multi-drug resistant TB
MRSA
SARS
pertussis (whooping cough)
Haiti cholera outbreak

56. Past Present future
Human genetic diversity
has never been greater

57. Past Present future Méle et al. (2012)
bination estimates of human effective population size · doi:10.1093/molbev/msr213
Africa Europe / Asia

58. Past Present future

59. Past Present future
http://www.nature.com/scitable/topicpage/ribosomes-transcription-and-translation-14120660

60. Past Present future

61. Past Present future
3.2 billion base pairs.

62. Past Present future
3.2 billion base pairs.
9 8
Mutation rate of 1.0 ⇥ 10 (2.3 ⇥ 10 ).

63. Past Present future
3.2 billion base pairs.
9 8
Mutation rate of 1.0 ⇥ 10 (2.3 ⇥ 10 ).
9
1.0 ⇥ 10 · 3.2 ⇥ 109 · 2 = 6.4 mutations per person.

64. Past Present future
3.2 billion base pairs.
9 8
Mutation rate of 1.0 ⇥ 10 (2.3 ⇥ 10 ).
9
1.0 ⇥ 10 · 3.2 ⇥ 109 · 2 = 6.4 mutations per person.
8
2.3 ⇥ 10 · 3.2 ⇥ 109 · 2 = 147.0 mutations per person.

65. Past Present future
3.2 billion base pairs.
9 8
Mutation rate of 1.0 ⇥ 10 (2.3 ⇥ 10 ).
9
1.0 ⇥ 10 · 3.2 ⇥ 109 · 2 = 6.4 mutations per person.
8
2.3 ⇥ 10 · 3.2 ⇥ 109 · 2 = 147.0 mutations per person.
⇡ 6.9 billion people as of mid-2010.

66. Past Present future
3.2 billion base pairs.
9 8
Mutation rate of 1.0 ⇥ 10 (2.3 ⇥ 10 ).
9
1.0 ⇥ 10 · 3.2 ⇥ 109 · 2 = 6.4 mutations per person.
8
2.3 ⇥ 10 · 3.2 ⇥ 109 · 2 = 147.0 mutations per person.
⇡ 6.9 billion people as of mid-2010.
About 3.6 billion of reproductive age.

67. Past Present future
22 billion to 529 billion
mutations per generation!

68. Past Present future
Mutation is the fuel of evolution
And the tank has never been fuller.

69. mutation
NATURAL selection
genetic drift
gene flow (migration)

70. mutation
NATURAL selection
genetic drift
gene flow (migration)

73. Thanks!