Table Of Content:
Winter 1993
13(2):149-169
Ethnobiol.
/.
MORPHOLOGY
THE EVOLUTION OF SEED IN
DOMESTICATED
dium
Chenop
o
AN STUDY
ARCHAEOLOGICAL CASE
GREMILLION
KRISTEN
J.
Department Anthropology
of
The Ohio University
State
OH
43210-1364
Columbus,
A has
ABSTRACT.— body data on several key morphological characters
large of
Chenopodium
of archaeological
been compiled through examination of collections
based on change in certain
from North America. Contrary to expectations
eastern
observed Chenopodium do not reflect
other seed crops, the patterns of variation in
Evidence
morphology away from the wild type. for
a gradual evolution of seed
domesticate
evolving like-
the is
morphological variability in
decreasing levels of
and crop
character of
demonstrate that the rate
wise minimal. These findings
can be expected to vary consid-
record
archaeological
evolution as revealed in the
among
erably taxa.
de Chenopodium
examen de colecciones
mediante
morfologicos clave el
teres
basadas
expectativas
Contrariamente a las
de Norteamerica.
arqueologico del este
de vanacion obser-
patrones
de semilla, los
en cambio en otros cultivos
ciertos
el
de
de morfologia las
gradual
una evolucion la
no
vados en Chenopodium reflejan
La evidencia de niveles decre-
del tipo silvestre.
en distancia
semillas creciente
domesticada en evolucion es
en especie
de morfologica la
variabilidad
cientes
que
demuestran que puede esperarse la tasa y
asimismo minima. Estos resultados
como en registro
se revela el
y
de cultivos, tal
de evolucion los
caracter
el la
taxa distintos.
entre
considerablemente
arqueologico, varien
mor-
characters
plusieurs
concernant
RESUME.-Un de donnees
ensemble
large
de Cheno-
des collections
examinant
en
phologiques importants a ete recueilli
basees sur les
aux expectatives
Contrairement
podium de de 1'Amerique.
1'est
de mor-
evolution
la
de graines cultivees,
especes
changements dans certaines 1
semble pas
ne
du sauvage
type
partir
Chenopodium a
de
phologie des graines
que
eviden
aussi le
observes. est
LL modeles de variation I
d'apres
progressive, les
^^^^Z^Z":ZZ
evident
morphologique
variable
de
vus
type
entre taxa.
considerablement
doivent varier
ologiques,
INTRODUCTION
econo^c,
sodal
and i,
_husbandry
p.an,
The and deve.opmen, of
origins
system
^™^.„
much nas txxii
etrort
Consequently, j ft
anthropologists.
to
Often the best evi-
production.
food
of
of the initiation
archaeological correlates
GREMILLION
No. 2
Vol.
150 13,
m
he form
of distinctive
domestication, frequently
anatomical
temporal markers
em
morDholoev
rreauentlv
more
morphology do an
cultigen hold considerable potential as empirical basi:
human com
inferences about various aspects of past behavior. For example,
tions of morphometric data from the eastern United States have been use
trace the intensification of relationships between humans and weedv anr
Smith
amenable examination
to
ma
linked domestication and and
to (such as fruit size seed coat thickness) the
by same
variability exhibited those have
characters. In particular, researchers
motivated
time
lishing a clear dichotomy between early and late forms. Also of interest whether
is
was
there tendency
a for domesticated populations be morphologically
to less
variable than wild and how
their relatives, so might be explained as a result
this
if
of selection in human-modified The
environments. answers questions
to these
regarding the path taken by crop evolution have important implications both for
the evolutionary and
history ecology of particular plant species and the study of
human
from North America
eastern
these research questions has accumulated
in recent years. Archaeological evi-
indicates
w-»*^,w "vvviji l,uuvl U1UIUU1J \JUllllWVtl,
XlL'IIMr»l'l»»f
-
annuus sumpweed,
annua and
L.; Iva chenopod Chenopodium
L.; or goosefoot,
Moq.) were
berlandieri brought under
domestication 1500
in the region before B.C.
Smith
(Crites
1993; 1987, 1989), although for chenopod the possibility of a Meso-
american
derivation remains be
to fully evaluated on phylogenetic grounds (Wil-
son
1981, 1990). In the case of sunflower and sumpweed,
evidence domestica-
for
form
tion takes the of a gradual
increase in achene has been observed in
size that
archaeological material (Asch and Asch
Smith
1985b; 1987; Yarnell 1972, 1978). In
domesticated
contrast,
taxa within Chenopodium from
are Drimarilv distinguished
com
linked
m
documented
America and
Smith
(Fritz
populations (Wilson
i 19
guishable from form
a
morphometric
data on North American
eastern
examination
The
forms. problem
addressed through
is first documentation changes the
of in
thickness of the seed and
coat other
characters thought be linked to
to closely
selection in the context of domestication. Next, evidpnrp reduction mor-
for in
JOURNAL OF ETHNOBIOLOGY
Winter 1993 151
domest
within
variability
temporal
implications of
]
human
behavior discu
are
RESEARCH
PREVIOUS
were
Chenopodium.—Chenopodium seeds
Establishment the domesticate status of
of
and abundant
and be both ubiquitous
found by Gilmore Jones (1936) to
(1931)
Kentucky and
the
among from dry rockshelters in eastern
organic materials
Ozark uplands. However, was not until the advent of flotation recovery of
it
Woodland
Eastern
remains the
in
common
number
appearance of maize in the archaeological record, interest
lized well before the
Com-
a>^ u^^^fKoci^orl inrKapnmiQ "Eastern Agricultural
..~~i ;~
:-i^i-
was
plex/'
It
m
examine evidence of distinctive
specimens
j
frequencies of certain traits
atypical
tendency display
lations, despite their to
margins
ma
domesticate status in
when misiden
previously
from wild ones
specimens
from
eliminated
Woodlands
Hugh
Wilson
by
pioneered
The reevaluation,
result of this
Smith
margin configura-
modifications of fruit
and associated
reduction of the seed coat
both extant cultivars of
distinguish
found
were to
and shape
tion cross-sectional
highland
crop of
a
nuttallme,
ssp.
berlandieri
Chenopodium (especially C.
berlandieri
Mex
Amer-
North
from eastern
specimens
between archaeological
blances were noted
coatand
dark seed
with a thin,
crop
'<*»' grain
and the cultivars (a
ica nuttalliae
pale-colored
and has small
maturation
before fruit
(which harvested
huazontle'
is
m
' absence of
of the
light
similarities
these
Despite
fruits) (Wilson 1981, 1990).
Mexica
was based
pnesmmnn, created
ssp.
new Chenopodium berlandieri
America
a taxon,
Ohio nd Rus^ll
Ash Cave
from .
collections
on wel.-preserved
descriptions of
,
Funk This discovery
and
Smith 1985).
1985b;
Alabama 1985a,
Cave, (Smith 1984,
on Chenopodjum serfs
dates
accelerator
was upplemented by 1500 B.C.)
early
(ca.
m
(Sm h
Kentucky
eastern
mckshelters
Qoudsplitter
Newt Kash and
from
the
™**^?£?°£Z^
the
that
Cowan established
and This finding
1987).
Wood and periods
Middle
and
Early
during the
crop
important cultivation of this
""£*£*» c
dunng
forms
domesticated
grew development of
an
out of **"•»»«»*
initial
morphologyand d
A the
concerning
information
synthesis of
concluded
and Smith
1988)
Chenopodium (Fritz
temporal and of cultigen
spatial)
GREMILLION
152 Vol. No. 2
13,
that, despite the present-day existence of conspecific cultivars in Mesoamerica,
the domestication of this species occurred locally and independently in the East-
ern Woodlands. However, some Wilson more
scholars consider
(e.g., 1981) likely
it
that the earliest domesticated chenopod in the Eastern Woodlands was a Meso-
american hoped
import. ongoing
that reconstruction of phylogenetic
It is rela-
among
North and South American
Wilson
(
question.
AND
DATA METHODS
—
The
data base. Analysis of several collections of well-preserved Chenopodium
mor
temporal
trends in seed
specimens
ot the cultigen type were examined
that
was
pale variety not Most ma
represented.
of these
Woodland
in
mate-
lie
remains
modern
samples
of Chenopodium was
berlandieri
m
placement specimens
of archaeological
crucial
is to interpreting patterns change and
of For
continuity
correctly. this
reason
contempora-
Newt
samples from
the
Kash
assumed
shelter are be
to associated with on
the 1500
ca. B.C. date directly
UMMA
number
catalog
occupation
represented on
is the site as well (Crane Unfortunately the
1956).
materials
were
methods
the
outlined
below.
In addition, data obtained from by other
analyses
researchers were
incorporated
into the present study comparative
chiefly for
purposes
(Table These
sources provided
1). important supplementary informa-
on
tion changing
patterns of variation in Chenopodium. They may be consulted for
more
complete
and
archaeological
methodological
information.
m
Analytic methods.—The
choice
of
domestication
m
forms
domesticated
domesticated
eliminating
the extended dormancy
ensured by impermeable
presence
of a thick,
germination
promotes
competition between
and
seedlings,
relatively early-maturing individuals are
more
-
JOURNAL OF ETHNOBIOLOGY
Winter 1993
153
oned
FIG.
1.
Smiling
Marble
Bluff;
Whitney White and Edens Bluff; 2, 3,
Bluff, Bluff,
Hammer
Cold Oak, and Thor's
Newt
Cave; Kash, Cloudsplitter,
Salts
5,
Cave.
Russell
Bone Westmoreland-Barber;
Cave: 7 Cave:
9,
Bit? 8.
germination
dormancy multiple
or
wild
Wet
(de
favorable
when conditions are
germinate environmental
con-
Harlan
mar;
producing truncate fruit
embrvo,
populations uanitn
wild
margins typical in
rounded
with biconvex or
trast the
„_
Wilson
1985a:59; 1981:237).
. .
.
both archaeologi-
A measurement of
morphometric
more
reported
frequently
alone
character
Although
this
diameter.
and modern Chenopodium seed
cal is
diameter
seed
forms,
domesticated
from
wild
cannot be used
to differentiate
sympatnc crop/
members
of
between
somewhat fashion
varies in a predictable
diameter the
seed
is
addition,
weed Smith 1985b). In
(Gremillion 1993a;
pairs
and thus provides a
specimens
archaeological
character most often recorded for
morphological variability.
general
assessing
and useful for
large varied data set that is
scanning
measured with the aid of a
was
specimens
most
Testa thickness of
Micro
Scanning Electron
the
located in
(Cambridge
electron microscope S-100)
Smithsonian Institution.
Museum Natural History,
scooe ahor, v National of
tor
I.
6
GREMILLION
154
No.
Vol. 2
13,
—
TABLE
Sample
information.
1.
Source
Context Sample Age
References
Samples
analyzed by
I. the author.
TN
Big Bone
Cave,
paleofeces Specimens
1, 2, 3, 600 ± 80 B.C. 3 Faulkner 1991;
and
8
Crothers 1987
KY
Salts Cave, SCU-140
paleofeces
290 ± 200 Watson
B.C.-
1974;
(Upper
Salts) SCU-106
620 ± 140 4
B.C. Yarnell 1969
SCU-41
Cave
Salts
Unit
KII
Flotation 250 ± 60 Gardner
B.C.- 1987
(Vestibule)
Level 5 sample +
620 5
70
1 B.C.
Oak
Cold
INV
Shelter,
grass-lined
124 640 ±
90
B.C.* O'Steen
et 1991;
al.
KY
storage
pit
Gremillion
1993c
Hammer
Thor's
INV
storage
pit 23 A.D. 880 ± 705
Gremillion 1993b
KY
Shelter,
Cloudsplitter
rock-lined FS
23
490 ± 80 Cowan
1 B.C.
1985a;
KY
Shelter,
storage
cist Cowan
1981;
et
al.
Cowan
Smith and
1987
Newt
UMMA
Kash
unknown;
Shelter,
16446, 1450 ± Cowan
150 Smith and
B.C.* 1987
KY
UMMA
paleofeces
16420
HDW
Michoacan,
Mexico
cultivated
5113A
modern
(Opopeo)
"chia
roja"
Mexico HDW
State
cultivated
5330 modern
(Santa Cruz)
pale-seeded
Published
II. data.
AL
Russell Cave,
grass-lined
FS. 23
390 ± 120
B.C.* Smith
1985a, 1985b,
storage
pit
unpublished
notes;
and
Fritz Smith 1988
OH
Ash
Cave,
storage
pit
A.D.
230 ± 1006 Smith
1985a,
unpublished
notes
Newt
Kash UMMA
Shelter, various
16440, 1500
B.C.- Asch and Asch
KY 1977;
16441, 16444 ^
700 5 7
B.C. Crane Smith and
- 1956;
16446, 16447
Cowan
1987
Smiling Dan,
IL various
700
B.C.-
Asch and Asch
1985a;
A.D. 2305 7
Sant and 1985
- Stafford
AR
Marble UAM
Bluff, buried
in
893 ± 44
5
B.C.
1986
Fritz
crevice
34-23-327
AR
Marble UAM
woven
Bluff, in
976 ± 40
B.C.s
and
Fritz 1986; Fritz
bag
34-23-341
Smith
1988
AR
White UAM
Bluff, gourd
in
10 ± 105
B.C.6
Fritz 1986
storage
pit
32-56-17a
AR
Edens UAM
Bluff,
in fiber
A.D.
20 ± 100"
1986
Fritz
bag
32-3-391
-
JOURNAL OF ETHNOBIOLOGY
Winter 1993
155
Source Context Sample1 Age2 References
UAM
AR
9
Whitney cached 1165 A.D. ± 75 Fritz 1986
Bluff, in
gourd
32-57-3a
UAM
1986
cached Fritz
in
bag
grass 32-57-5c
HDW5113, modern Smith 1985b
Michoacan, Mexico
cultivated
5115,5116
HDW
SCU
Hugh Upper
by Wilson; =
Sample numbers preceded by were collected
Abbreviations:
UAM
UMMA
= Museum Anthropology; = University of
Michigan of
Cave; University of
Salts
INV number.
Arkansas Museum; FS = Sample; = Inventory
Field
2 A11 radiocarbon dates are uncalibrated.
specimens.
Accelerator date obtained from one of these paleofecal
4Beta decay date on other paleofeces from Upper Salts Cave.
5Beta decay date on associated material.
Accelerator date on associated Chenopodium.
Estimate based on radiocarbon dates.
a series of
8
Beta decay date on associated Chenopodium.
Accelerator date on associated material.
SEM
similar
Hammer and Cold Oak were studied at a
Materials from Thor's
Chapel
North Carolina,
of
University
Department Pathology,
of
facility in the
tape or a solution
double-stick
using either
Specimens were stubs
affixed to
Hill.
sputter-coated
They were then
and water.
of white water-based glue (Elvace)
magni-
standard
measured a
were at
Most seeds
with gold/palladium mixture.
a
Kv Becau e
mm) illumination.
using 10
and working distance (36
X)
fication (450
^dividual
on an fruit,
between regions
somewhat
seed —
coat thickness varies
rrncc-QPrtion of the testa tar-
1.1 ^
.
measurements
from
Modern were sectioned
fruits
more
were
Margin
ma
~~~
~
wnn ovw vm ~
upward ana »
tne oeaK 6
• ma lower
form of tne g
the
was according to
then placed a category
in
were based oi
classification
for
Criteria
most part of the of view (Fig. 2b).
field
Smith
illustrations in (19£
v*»«~,—
-,.
sectioning.
alter
somewhat figuration
margi
different
manner described
the
in
sectioning
made
prior to
^
^
above.
Maximum
««
magm »n ^
.can
under low
calibrated glass slide
.
^_ m L
d
.zahon reduce */lL
appears l
to
were restricted
which
seeds,
ni
measurements
made
to
sample from
1
GREMILLION
No.
156 Vol. 2
13,
beak
1
i i
FIG.
2.
assessment
measurement
assessment margin
of
face to the
right).
JOURNAL OF ETHNOBIOLOGY
Winter 1993 157
—
Subsampling and seed categories. In the case of archaeological Chenopodium seeds,
specimens from a given provenience intact enough to permit assessment of the
all
modern
characters described above were combined to form an analytic sample. For
mature specimens were randomly Further sub-
populations, selected for analysis.
was samples were dimorphic.
division applied to those archaeological that clearly
The "weed morph" associated with free-living
exhibits a suite of characteristics
wild and/or weedy) Chenopodium but not with contemporary domesticated
(e.g.,
and prominently patterned
populations. These characteristics include a thick
prominent
Only specimens
margins.
from
eliminated
and
diameter
supported by the significant differences in
distinction statistically
is
mor
AND
HUSBANDRY
TEMPORAL PLANT
TRENDS
IN
The
domestication
fact that
they
m
from
the
species to species,
from
wild
their
features related
structural
environments. Thus, they share certain
in
dormancy
Another trend frequently rec-
Hamblin
mechanisms (Donald and 1983).
dispersal
within
genetic variability
reduction of
ognized an outcome domestication
as of is
predictability
may the relative
reflect
crop This trend
populations (Bennett
1970).
as intentional selec-
well
ecosystem as
human-managed
and
homogeneity
of the
seedstock.
tion of consistently favored traits in
the
populations
change crop ,s
in
The and evolutionary
character of
rate
phenotyp
and c
their
between heritable traits
product complex
of the interactions
resul
does not necessarily
change
Genetic
environments.
expression
particular
in
morphological
and
characteristics,
phenotypic
in corresponding alteration of
imperfect
Despite this
cause.
genetic
an underlying
variation need not represent
and
heir
upon seed characters
selection
between operation of
relationship the
sfo
link-
^*<»^exi^st ™^
ification
and empirical just
good
phenotypic theoretical
expression,
morphology with selection
ing
certain aspects of
evolution.
crop
evidence for
one source of
as
archaeological record can be enlisted
%£Z
*
8*"£^°£
-Reduction
Change
domestication.
in characters linked to
enhancement
minating
human-ma
na
Wet
ffiS^iSE^^S^
some
implies
time
over
these traits
intensification of selection for
incremental
an
and/or in
sam
GREMILLION
No.
Vol. 2
158 13,
—
TABLE
domesticated Chenopodium.
2. Testa thickness statistics,
Thickness (Microns)
Testa
Mean
Period Site/Sample S.D. 1 C.V 2 n
Newt
Kash
Late Archaic (16420) 15.8 2.0 12.7 10
Newt
(1500-1000 Kash
B.C.) (16446) 20.7 11.7 56.4 10
Woodland
Early Salts Vestibule 10.5 5.5 52.8 11
(1000-300 Upper
B.C.) Salts 13.3 4.9 37.1 38
SCU-1 40
8
13.8 4.8 34.6
SCU-106
20
13.9 5.7 41.2
SCU-41
11.7 3.0 25.6 10
Oak
Cold
14
13.0 2.6 30.9
Cloudsplitter 14
13.0 2.6 20.3
Cave
Russell 20
11.3 2.8 23.8
Bone Cave3
Big 35
21.2 4.7 22.3
Middle Woodland Ash
Cave
20
14.9 3.0 20.3
(200 B.C-A.D.
500)
Woodland Hammer
Late
Thor's
13.9 4.9 35.5 21
(A.D. 500-1000)
HDW
Modern
5115
5113, 20
16.3 3.8 23.1
HDW5113A
cultivars
10
18.6 3.5 18.6
-
^.d. Standard
deviation
2 =
c.v. coefficient of variation
Specimens
and
1, 2, 3.
domesticated chenopod
from Woodlands
the Eastern varies
reflects selection reduced dormancy
i it for during incipient
(UMMA
on One
(Table sample Newt
from Kash
2). shelter
mean
tively high
Cheno-
testa thickness
values. Similarly,
from Marble
LIU
^^ ^^ * ^"* * A l * A. A A\Vi A l/U ij ^4 CI £L I V ' ^^ V^ • * ^-^ ^^ ^"^
ft
was
B.C. described
as having somewhat
thicker seed coats than collections
later
samples among
are the most
some
compares
favorably
in overall morphology
with modern Mexican Thus,
cultivars.
although some
early
material
resembles
wild
forms (whose thickness typ-
testa
ically averages above
40
microns; Smith
the
1985b), other (including
collections
known
earliest
thin-testa
fruits) are
virtually
respect
indistinguishable
in this
from modern
cultivars.
The
absence
of a
directional
trend
demonstrated by between
is the correlation
and
testa thickness
estimated sample =
age
for data in Table which near (r
2, is
N
-0.05, - =
p 0.88, 12) (Fig. Thus,
3a). there no
evidence thickness
is that seed coat
was
reduced
in a gradual,
linear fashion Woodland
in the Throughout
past. the
period 1000-300 mean
(ca.
B.C.), 10-
testa thickness
values remain the
primarily in
F
20 micron nn
ranee.
In fart arrhao«i«™„.,ii.. :li. ...
j.
..• L
,
