Acta Zoologica,
Journal Year:
2018,
Volume and Issue:
100(4), P. 359 - 364
Published: May 29, 2018
Abstract
Although
different
mechanisms
exist
to
explain
the
presence
of
polymorphism
in
lizards,
one
model
suggests
that
multiple
morphotypes
display
same
level
fitness.
Three
male
morphs
(grey,
yellow
and
orange)
coexist
Sceloporus
aeneus
,
a
Mexican
endemic
oviparous
lizard.
Using
histological
perspective,
we
test
hypothesis
spermatogenic
output
does
not
vary
across
S
.
during
its
maximum
testicular
activity.
Males
(five
grey,
five
were
collected
Calimaya,
Estado
de
México,
Mexico.
Snout‐vent
length
(
SVL
),
testis
mass,
diameter
epithelial
heights
for
seminiferous
tubules
epididymis,
number
layers
germ
cells
did
among
morphs;
moreover,
according
principal
component
analysis,
high
overlap
lateral
colour
exists.
Our
results
suggest
strongly
have
output,
natural
selection
may
be
stronger
driving
force
than
sexual
within
this
species.
Further
studies
into
other
lizard
species
with
are
required
determine
whether
lack
variation
observed
is
consistent
polymorphic
which
will
provide
greater
understanding
selective
acting
on
an
individual’s
Biological Journal of the Linnean Society,
Journal Year:
2016,
Volume and Issue:
119(4), P. 932 - 942
Published: July 14, 2016
Understanding
pre-
and
post-copulatory
mechanisms
of
sexual
selection
can
provide
insights
into
the
evolution
male
reproductive
strategies.
The
phenotype-linked
fertility
hypothesis
postulates
that
sperm
quality
secondary
characteristics
will
positively
co-vary,
whereas
competition
predicts
a
negative
association
between
those
traits.
Male
traits
often
show
variation
throughout
period,
suggesting
relationship
may
vary
temporally.
Here,
we
evaluated
character
its
temporal
in
Salvator
rufescens,
south
American
lizard.
We
observed
jaw
muscle
principal
piece
length
period.
Collectively,
our
results
evidenced
trade-off
strong
seasonal
flexibility
strategies
this
lizard
species.
South American Journal of Herpetology,
Journal Year:
2015,
Volume and Issue:
10(2), P. 132 - 142
Published: Aug. 1, 2015
Segregation
of
habitat
resources
is
an
important
mechanism
that
allows
the
coexistence
species.
The
diet
and
dynamic
component
can
generate
interactions
among
co-existing
Differences
in
food
resource
use
between
related
sympatric
species
have
been
associated
frequently
with
divergence
multiple
phenotypic
traits;
hence,
it
interesting
to
explore
how
differences
allow
minimize
niche
overlap.
We
aimed
evaluate
trophic
segregation
Tupinambis
merianae
T.
rufescens
relation
life
history
traits
a
zone.
compared
volume
stomach
items
considering
sexual
dimorphism,
body
size
classes,
maturity
reproductive
activity.
obtained
Morisita's
index
indicated
overlap
rufescens;
however,
particular
items,
we
observed
composition.
Moreover,
our
results
indicate
size,
activity
are
relevant
factors
influencing
these
Life
two
because
they
shape
composition,
contributing
interspecific
and,
therefore,
allowing
coexistence.
PeerJ,
Journal Year:
2015,
Volume and Issue:
3, P. e1478 - e1478
Published: Dec. 8, 2015
Studies
concerning
the
relationships
between
sperm
size
and
velocity
at
intraspecific
level
are
quite
limited
often
yielded
contradictory
results
across
animal
kingdom.
Intramale
variation
in
may
represent
a
meaningful
factor
to
predict
velocity,
due
its
relationship
with
of
competition
among
related
taxa.
Because
phenotype
is
under
post-copulatory
sexual
selection,
we
hypothesized
that
reduced
intramale
associated
competitiveness
red
deer.
Our
show
low
strongly
high
normal
morphology,
which
turn
good
predictors
male
fertility
this
species.
Furthermore,
it
well
known
deer
variability
testicular
mass
but
there
knowledge
significance
phenomenon
level,
even
though
reveal
interesting
processes
selection.
Thereby,
as
preliminary
result,
found
absolute
testes
negatively
size.
findings
suggest
strong
selective
force
leading
increase
function
efficiency,
new
insights
into
selection
mechanisms.
Biological Journal of the Linnean Society,
Journal Year:
2017,
Volume and Issue:
121(2), P. 355 - 364
Published: Feb. 14, 2017
Previous
studies
demonstrated
that
variation
in
sperm
morphology
exists
below
the
species
level
a
variety
of
organisms.
However,
most
focus
on
invertebrates
with
only
few
recent
vertebrates
majority
birds
and
mammals.
Understanding
at
various
taxonomic
levels
is
necessary
for
comparative
studies.
Therefore,
to
test
hypothesis
shows
little
between
within
closely
related
taxa,
was
analyzed
multiple
populations
two
sister
lizards,
Sceloporus
consobrinus
undulatus.
The
ultrastructure
did
not
differ
intraspecifically
nor
interspecifically,
but
differences
were
observed
morphometrics
populations.
data
gathered
this
study
show
spermatozoa
consistent
other
squamates,
although
no
slight
variations
when
compared
members
Phrynosoma.
size
differs
despite
there
may
be
selection
Biology Open,
Journal Year:
2021,
Volume and Issue:
10(4)
Published: March 18, 2021
Global
warming
is
affecting
biodiversity;
however,
the
extent
to
which
animal
reproductive
processes
respond
predicted
temperature
increments
remains
largely
unexplored.
The
thermal
environment
has
a
pronounced
impact
on
metabolic
rates
of
ectotherms;
therefore,
an
interesting
question
assess
whether
increase
might
affect
specific
mechanisms
like
sperm
performance
in
ectotherms.
Moreover,
many
species,
oviductal
fluid
(OF)
known
regulate
and
maintain
quality;
role
OF
relation
effects
high
unclear.
Our
aim
was
experimentally
test
effect
increased
velocity,
swimming
path
percentage
motility
neutral
conditions
at
ejaculation
(without
OF)
female's
tract
(with
OF),
social
ectotherm
lizard
model,
Tropidurus
spinulosus,
requirements
for
reproduction.
results
suggest
that
rising
associated
with
global
(+4°C)
affects
negatively
dynamics
survival.
However,
ameliorated
harmful
temperature.
This
important
point,
as
this
study
first
have
tested
preserving
from
warmer
pre-fertilization
environment.
These
contribute
our
understanding
how
changes
post-copulatory
mechanisms.
article
First
Person
interview
author
paper.
Molecular Reproduction and Development,
Journal Year:
2021,
Volume and Issue:
88(6), P. 416 - 426
Published: May 19, 2021
Abstract
The
effect
of
inbreeding
depression
on
sperm
motility
is
well
documented,
but
its
influence
morphometry
has
been
scarcely
examined
to
date.
Here,
we
combined
the
use
computer‐assisted
analysis
(CASMA)
with
a
SNP‐based
genomic
approach
determine
and
characterize
shape
highly
inbred
cattle
population.
We
determined
seven
morphometric
parameters
frozen‐thawed
samples
57
Retinta
bulls:
length
(L,
µm),
width
(W,
area
(A,
µm
2
),
perimeter
(P,
ellipticity
(ELI;
L/W),
elongation
(L−W)/(L
+
W)
perimeter‐to‐area
factor
(p2a;
P
/4
×
π
A).
comparison
(HI)
lowly
inbreed
(LI)
individuals
based
runs
homozygosity
(ROH)
values
(
F
ROH
)
showed
no
differences
between
groups.
An
additional
two‐step
unsupervised
subpopulation
significant
in
abundance
different
subpopulations
groups
p
<
0.05).
This
revealed
that
HI
bulls
harbored
higher
percentage
narrow‐head
as
opposed
large‐
round‐headed
detected
LI.
A
further
characterization
23
regions
differentially
affected
by
both
groups,
detecting
six
genes
SPAG6,
ARMC3,
PARK7,
VAMP3,
DYNLRB2,
PHF7)
previously
related
spermatogenesis‐associated
processes.
