Animal Diversity Mimic Octopus Paper

Question 1

The ‘mimic octopus’ emerges during … hours to forage on … … in full view of … fish predators.

Answer 1

daylight, sand substrates, pelagic

Question 2

This study observed … individuals of this species displaying a repertoire of postures and body patterns, several of which are clearly impersonations of … animals co-occurring in this habitat

Answer 2

nine, venomous

Question 3

This ‘… mimicry’ avoids the genetic constraints that may limit the diversity of genetically … mimics but has the same effect of decreasing the … with which predators encounter particular mimics.

Answer 3

dynamic, polymorphic, frequency

Question 4

The observations suggested that the octopus makes decisions about the most … form of mimicry to use, allowing it to enhance further the benefits of mimicking toxic models by employing mimicry according to
the nature of perceived threats.

Answer 4

appropriate

Question 5

Before the discovery of the mimic octopus, no
animal of any group had previously been described that is
able to…

Answer 5

switch back and forth between mimicry of

different model organisms.

Question 6

The ‘mimic octopus’ has an arm span of up to …,
and was discovered in … off the coast of Sulawesi,
….

Answer 6

60cm, 1998, Indonesia

Question 7

It is found on … and … substrates off river mouths in
water between 2m and 12m deep. This habitat is rich in
… infauna with a high activity of worms, echinoderms, crustaceans and fishes, riddling the sea-floor with
burrows, tunnels and mounds.

Answer 7

silt, sand, benthic

Question 8

Mimic octopuses are typically encountered sitting in

the … … … on sand or silt mounds.

Answer 8

mouths of burrows

Question 9

Foraging individuals typically crawled along the

substrate in … … colours, using their … … to probe down holes and the flared webs to trap fleeing prey

Answer 9

drab brown, arm tips

Question 10

When moving faster (using … …), the octopus drew all its arms into a …-… wedge with a central mantle trailing the head. In this form it swam between worm mounds, … the body in the fashion of a swimming …. We believe that this unique posture is mimicry of an abundant … found in this habitat

Answer 10

jet propulsion, leaf-shaped, undulating, flatfish, sole

Question 11

Four individuals were observed swimming just above the sea-floor with arms trailing from the body, taking on the appearance of a … (Pterois spp) swimming with its banded poisonous spines fully flared.

Answer 11

lionfish

Question 12

On four occasions, attacks by small territorial damselfishes (Amphiprion spp.) elicited a posture where … arms were threaded down a hole and two were raised in opposite directions, banded, curled and undulated, to produce the appearance of a … … …

Answer 12

six, banded sea snake

Question 13

The majority of individuals also used general background … patterns in response to certain passing predatory fishes

Answer 13

camouflage

Question 14

Other distinctive behaviours were observed, including sitting on top of sand mounds and raising all the arms above the body, each arm being held in a zigzag form. It is
possible that this posture impersonates large solitary
… … (such as Megalactis spp.) that are armed
with powerful stinging cells (…)

Answer 14

sand anemones, nematocysts

Question 15

In another incident, a large female (arm span, 60 cm) swam to the sea surface from 4 m deep, then slowly sank with undulating arms spread evenly around the animal. This behaviour may impersonate large … found in the
region.

Answer 15

jellyfishes

Question 16

In addition to typical … foraging (threading long arms down burrows and holes to seize fishes and crustacean prey), animals were observed to enter a tunnel completely and to … from another hole up to … from the entrance point. As of 2001 scientists were unaware of any other octopuses that forage through … tunnels.

Answer 16

speculative, emerge, 1m, subterranean

Question 17

Polymorphism in … mimics is rare, and unlikely on theoretical grounds. Rare forms are strongly selected against, because … are less likely to have learnt to avoid them.

Answer 17

Mullerian, predators

Question 18

One possible explanation for the rarity of polymorphic Batesian mimics is frequent selection towards the most … or … model.
Alternatively, polymorphism may be rare because of the tight … between mimicry genes that is necessary to prevent recombination breaking up the coadapted complex.

Answer 18

noxious, abundant, linkage

Question 19

The ‘… mimicry’ (Norman et al. 1999) of the mimic octopus may escape this genetic constraint because it is not employed …: all individuals can carry alleles for all forms of mimicry ….
This has been described as a ‘… polymorphism’,
whereby cephalopods gain the benefits of polymorphism,
such as increased apparent rarity, without genetic polymorphism

Answer 19

dynamic, continuously, simultaneously, neural

Question 20

It is likely that dynamic mimicry is only possible due to several key attributes of cephalopods in general and octopuses in particular. The absence of a … internal or external … reduces physical restrictions to adopting different shapes, and the octopus’s ability to change the colour, pattern and shape of its … makes it uniquely adapted to complex forms of mimicry.

Answer 20

rigid, skeleton, skin

Question 21

Although it is likely that the mimic octopus’s behaviour
is the result of natural selection, it is worth considering
the possibility that it may also be … selected.
Complex behaviours may simply be … displays
misinterpreted as mimicry.
However, at present there is no evidence to support this possibility: both … show mimicry behaviour, all animals were well separated (50^100 m apart) and all displays were observed in the absence of ….

Answer 21

sexually, courtship, sexes, conspecifics

Question 22

The open sand and mud habitat of the mimic octopus is a
particularly exposed and …-… environment, and
may explain why mimicry has evolved in this species.

Answer 22

predator-rich