Growing out of the fins: Implications of isometric and allometric scaling of morphology relative to increasing mass in blue sharks (Prionace glauca)
Zoology,
Journal Year:
2024,
Volume and Issue:
165, P. 126184 - 126184
Published: June 14, 2024
Language: Английский
Growing out of the fins: implications of isometric and allometric scaling of morphology relative to increasing mass in blue sharks (Prionace glauca)
bioRxiv (Cold Spring Harbor Laboratory),
Journal Year:
2023,
Volume and Issue:
unknown
Published: Dec. 23, 2023
ABSTRACT
Disproportional
changes
(i.e.
allometry)
in
shark
morphology
have
been
attributed
to
shifts
function
associated
with
niche
life
history,
such
as
habitat
and
diet.
Photographs
of
blue
sharks
(
Prionace
glauca,
26-145
kg)
were
used
analyze
parameters
body
fin
increasing
mass
that
are
fundamental
swimming
feeding.
We
hypothesized
would
demonstrate
proportional
isometry)
because
they
do
not
undergo
profound
prey
type,
but
a
result,
we
predicted
grow
into
bodies
greater
turning
inertias
smaller
frontal
surface
areas,
addition
spans
areas
the
fins
relative
mass.
Many
aspects
increased
isometry.
However,
demonstrated
negative
allometry
density,
whereas
area,
volume
roll
inertia
body,
span
aspect
ratio
both
dorsal
fins,
ventral
caudal
fin,
span,
length
area
mouth
positive
allometry.
The
dataset
was
divided
half
based
on
form
two
groups:
larger
sharks.
Besides
mass,
had
significantly
compared
Hence,
isometric
scaling
does
necessarily
imply
functional
similarity,
allometric
may
sometimes
be
critical
maintaining,
rather
than
shifting,
Both
promote
reduced
costs
transport
migration,
conversely,
decreased
unsteady
performance,
escape
responses.
These
likely
beneficial
for
probably
experience
reductions
predation
pressure.
Language: Английский
Insights into ontogenetic scaling and morphological variation in sharks from near-term brown smooth-hound (Mustelus henlei) embryos
bioRxiv (Cold Spring Harbor Laboratory),
Journal Year:
2024,
Volume and Issue:
unknown
Published: Feb. 6, 2024
Abstract
Elasmobranchs
(sharks
and
rays)
exhibit
a
wide
range
of
body
forms
adapted
to
various
ecological
niches.
Body
form
differs
not
only
between
species,
but
life
stages
individual
species
as
result
ontogenetic
allometry.
In
sharks,
it
has
been
proposed
that
these
shifts
in
from
trophic
and/or
spatial
ecology
(the
allometric
niche
shift
hypothesis).
Alternatively,
suggested
allometry
may
intrinsic
morphological
constraints
associated
with
increasing
size
–
e.g.
counteract
form-function
relationships
occur
function
could
compromise
locomotory
performance.
One
major
limitation
affecting
our
understanding
scaling
sharks
is
existing
studies
focus
on
postpartum
ontogeny
ignoring
the
period
growth
occurs
prior
birth/hatching.
this
study,
we
report
trajectories
39
near-term
brown
smooth
hound
(
Mustelus
henlei
)
embryos
taken
manually
collected
measurements.
We
found
unlike
most
other
later
M.
,
predominantly
grow
isometrically,
appear
display
relatively
high
levels
disparity.
These
results
provide
rudimentary
support
for
hypothesis
(as
absence
isometry
dominates
body-form
scaling)
important
insight
into
early
shark
morphological/developmental
evolution.
Language: Английский
Allometric Growth and Scaling of Body Form of the Spadenose Shark (Scoliodon laticaudus)
Ecology and Evolution,
Journal Year:
2024,
Volume and Issue:
14(10)
Published: Oct. 1, 2024
The
versatility
of
the
shark
body
form
is
suggested
to
be
one
key
factors
underlying
their
evolutionary
success
and
persistence.
Nevertheless,
sharks
exhibit
a
huge
diversity
forms
morphological
adaptations.
More
subtly,
it
increasingly
evident
that
in
many
species,
morphology
varies
through
ontogeny.
Multiple
competing
hypotheses
exist
explaining
both
function
specific
structures
interspecific
distribution
these
ontogenetic
shifts.
However,
existing
studies
are
restricted
small
number
mostly
large-bodied
species.
In
this
study,
we
report
allometric
scaling
relationships
from
functionally
important
spadenose
(
Language: Английский
The largest to the south? Assessment of the latitudinal variation in Mustelus schmitti (Chondrichthyes: Carcharhiniforms: Triakidae), an endemic coastal shark of the Southwest Atlantic Ocean
Biological Journal of the Linnean Society,
Journal Year:
2024,
Volume and Issue:
143(3)
Published: Nov. 1, 2024
Abstract
Relative
growth
and
life
history
traits
along
latitudinal
gradients
have
been
widely
examined
in
bony
fishes,
but
chondrichthyans
received
less
attention.
The
present
work
focuses
on
testing
whether
southern
distributed
individuals
of
Mustelus
schmitti
sharks
are
larger
will
mature
at
sizes
than
northern
individuals.
We
also
show
that
intraspecific
variation
follows
the
pattern
body
shape
proportions
not
altered
by
distribution.
specimens
come
from
two
areas
1200
km
apart
[Puerto
Quequén
(PQ)
Ria
Deseado
(Deseado
estuary)
(PD)],
which
implies
9
degrees
difference.
For
PQ,
four
allometric
variables
related
to
trunk
showed
secondary
sexual
dimorphism,
while
for
PD
this
dimorphism
was
observed
a
single
variable.
females
PQ
presented
with
higher
relative
PD.
Males,
contrast,
did
characteristic
could
differentiate
between
areas.
Specimens
both
sexes
reached
average
total
length
first
maturity
(P
<
.05)
those
PQ.
Language: Английский
Heterochrony and Oophagy Underlie the Evolution of Giant Filter‐Feeding Lamniform Sharks
Evolution & Development,
Journal Year:
2024,
Volume and Issue:
27(1)
Published: Nov. 30, 2024
ABSTRACT
Evolutionary
transitions
toward
gigantic
body
sizes
have
profound
consequences
for
the
structure
and
dynamics
of
ecological
networks.
Among
elasmobranchs
(sharks
rays),
gigantism
has
evolved
on
several
occasions,
most
notably
in
iconic
Megalodon
(
Otodus
megalodon
†)
extant
whale
shark
Rhincodon
typus
),
basking
Cetorhinus
maximus
megamouth
Megachasma
pelagios
all
which
reach
total
lengths
exceeding
6
m
and,
some
cases,
21
or
more.
Comparative
phylogenetic
studies
suggest
that
filter
feeding
heterothermy
provide
two
alternative
evolutionary
pathways
leading
to
sharks.
These
selection‐based
explanations
are
important;
however,
our
understanding
size
is
fundamentally
constrained
without
a
proximate,
mechanistic
how
suite
adaptations
necessary
facilitate
evolved.
Here
we
propose
heterochrony
hypothesis
evolution
giant
filter‐feeding
ecomorphotype.
We
craniofacial
oophagy
embryonic
stages
lamniform
sharks
retained
through
ontogeny
C.
M.
by
paedomorphosis,
resulting
an
enlarged
head
mouth
relative
rest
body,
even
adulthood.
This
change
developmental
timing
enables
these
taxa
optimize
prey
acquisition,
thought
be
limiting
factor
marine
vertebrates.
discuss
concordance
this
with
current
developmental,
morphological,
data,
future
means
could
tested.
Language: Английский