scholarly journals Cuttlefish show flexible and future-dependent foraging cognition

2020 ◽  
Vol 16 (2) ◽  
pp. 20190743 ◽  
Author(s):  
Pauline Billard ◽  
Alexandra K. Schnell ◽  
Nicola S. Clayton ◽  
Christelle Jozet-Alves
Keyword(s):  
Food Availability ◽  
Feeding Behaviour ◽  
Foraging Behaviour ◽  
Foraging Strategy ◽  
The Other ◽  
Foraging Activity ◽  
Experimental Conditions

Some animals optimize their foraging activity by learning and memorizing food availability, in terms of quantity and quality, and adapt their feeding behaviour accordingly. Here, we investigated whether cuttlefish flexibly adapt their foraging behaviour according to the availability of their preferred prey. In Experiment 1, cuttlefish switched from a selective to an opportunistic foraging strategy (or vice versa ) when the availability of their preferred prey at night was predictable versus unpredictable. In Experiment 2, cuttlefish exhibited day-to-day foraging flexibility, in response to experiencing changes in the proximate future (i.e. preferred prey available on alternate nights). In Experiment 1, the number of crabs eaten during the day decreased when shrimp (i.e. preferred food) were predictably available at night, while the consumption of crabs during the day was maintained when shrimp availability was unpredictable. Cuttlefish quickly shifted from one strategy to the other, when experimental conditions were reversed. In Experiment 2, cuttlefish only reduced their consumption of crabs during the daytime when shrimps were predictably available the following night. Their daytime foraging behaviour appeared dependent on shrimps' future availability. Overall, cuttlefish can adopt dynamic and flexible foraging behaviours including selective, opportunistic and future-dependent strategies, in response to changing foraging conditions.

scholarly journals Adaptations of two Intertidal Isopods II. Comparison between Campecopea Hirsuta and NAESA BIDENTATA (Sphaeromatidae)

1963 ◽  
Vol 43 (1) ◽  
pp. 97-112 ◽  
Author(s):  
Wolfgang Wieser
Keyword(s):  
Feeding Behaviour ◽  
Middle Part ◽  
The Other ◽  
Way Of Life ◽  
Experimental Conditions ◽  
Endogenous Rhythms ◽  
Endogenous Factors ◽  
Blue Green Algae ◽  
Preferred Habitat ◽  
The Vertical Distribution

In the investigation described in this paper, respiration, resistance to desiccation and feeding behaviour of .the mid- to upper-tidal isopod Campecopea hirsuta was studied and compared with the analogous parameters of behaviour in the lower intertidal species Naesa bidentataC. hirsuta occurs in the middle part of the shore where it can be found within empty shells of Chthamalus. Its preferred habitat, however, is the lichen Lichina pygmaea the vertical distribution of which extends from OD to MHWS.Campecopea hirsuta feeds on the blue-green algae that make up the outer layer of the lichen L. pygmaea. When continuously submerged the isopod feeds in bursts, the timing of which is different in different specimens. This mode of feeding under experimental conditions is taken as reflecting the rhythmic way of life of this species in its natural environment but it seems to be controlled by endogenous factors. Naesa bidentata, on the other hand, does not display such endogenous rhythms in its feeding behaviour.

The influence of wing morphology and echolocation on the gleaning ability of the insectivorous bat Myotis tricolor

2004 ◽  
Vol 82 (12) ◽  
pp. 1854-1863 ◽  
Author(s):  
Samantha Stoffberg ◽  
David S Jacobs
Keyword(s):  
Discriminant Analysis ◽  
Foraging Behaviour ◽  
Myotis Lucifugus ◽  
The Other ◽  
Wing Morphology ◽  
Echolocation Calls ◽  
Narrow Bandwidth ◽  
Mole Crickets ◽  
Wing Tips ◽  
Wing Tip

On the basis of its external morphology, Myotis tricolor (Temminck, 1832) should be able to both aerial-feed and glean. Furthermore, this bat is known to use broadband calls of short duration, reinforcing the prediction that it gleans. However, results from this study indicate that M. tricolor does not commonly glean. This conclusion was reached after studying the foraging behaviour of M. tricolor in a flight room. We presented M. tricolor with mealworms, moths, mole crickets, beetles, and cicadas in a variety of ways that required either gleaning and (or) aerial feeding. Although M. tricolor readily took tethered prey, it did not take any of the variety of insects presented to it in a manner that required gleaning. We therefore compared its wing morphology and echolocation calls with those of several known gleaners, Nycteris thebaica E. Geoffroy, 1818, Myotis lucifugus (Le Conte, 1831), and Myotis septentrionalis (Trouessart, 1897), and an aerial forager, Neoromicia capensis (A. Smith, 1829). In a discriminant analysis wing-tip shape was the only variable to provide some degree of discrimination between species, with M. tricolor having more pointed wing tips than the known gleaners. Discriminant analysis of echolocation-call parameters grouped M. tricolor with the other Myotis species and separated it from N. capensis and N. thebaica. However, M. tricolor did not use harmonics as did the other Myotis species. The apparent failure of M. tricolor to glean might therefore be due to its relatively pointed wings and narrow-bandwidth echolocation calls, owing to the absence of harmonics in its calls.

Intercalation Processes in Cobalt Substituted Nickel Oxyhydroxides

1990 ◽  
Vol 210 ◽  
Author(s):  
Claude Delmas
Keyword(s):  
Ir Spectroscopy ◽  
Mechanical Treatment ◽  
Positive Charge ◽  
Van Der Waals ◽  
The Other ◽  
Hydrolysis Reaction ◽  
Water Molecules ◽  
Layered Oxides ◽  
Experimental Conditions ◽  
Cobalt Ions

AbstractChimie douce reactions (hydrolysis and reduction) from layered oxides : NaNiO2, NaxCoO2 and NaNil-xCoxO2 lead to numerous oxyhydroxides and hydroxides which differ by the composition of the intersheet space.According to the experimental conditions of the hydrolysis reaction, the oxyhydroxides can be unhydrated or intercalated with one or two layers of water molecules. From the most hydrated phases, the other ones can be obtained by chemical, thermal and even mechanical treatment.The reduction of Co-substituted nickel oxyhydroxides leads to hydroxides in which nickel and cobalt ions are respectively divalent and trivalent. In order to compensate the excess of positive charge in the (Ni, Co)O2 sheet, anions (OH-, CO32-, SO42-, NO3-) are inserted in the Van der Waals gap.For the highest anion amounts, well ordered α*-type materials are obtained. Water molecules are simultaneously inserted in the interslab space. Their structure is strongly related to the hydrotalcite one. When the amouit of anions in the intersheet space is not sufficient, interstratified materials are obtained. In this case the (Ni,Co)(OH)2 slabs are separated by a layer of CO32- anions and water molecules (α*-type) or by an empty Van der Waals gap (β(II)-type). The amount of α*-type planes in the structure increases with the cobalt amount. All these materials have been characterized by IR spectroscopy which allows to detect the existence of two types of O-H bonds (free in α*-type plane or hydrogen bonded in ²(II)-type plane).

The feeding behaviour of large perch Perca fluviatilis (L.) in relation to food availability: a comparative study

Hydrobiologia ◽  
2003 ◽  
Vol 506-509 (1-3) ◽  
pp. 427-434 ◽  
Author(s):  
Hendrik Dörner ◽  
Søren Berg ◽  
Lene Jacobsen ◽  
Stephan Hülsmann ◽  
Mads Brojerg ◽  
...  
Keyword(s):  
Comparative Study ◽  
Food Availability ◽  
Feeding Behaviour ◽  
Perca Fluviatilis ◽  
Perch Perca Fluviatilis

In Vitro Binding of Zearalenone to Different Adsorbents

2005 ◽  
Vol 68 (3) ◽  
pp. 613-615 ◽  
Author(s):  
DANTE J. BUENO ◽  
LILIANA DI MARCO ◽  
GUILLERMO OLIVER ◽  
ALICIA BARDÓN
Keyword(s):  
Activated Carbon ◽  
Calcium Sulfate ◽  
Fusarium Species ◽  
The Other ◽  
Experimental Conditions ◽  
In Vitro Binding ◽  
Other Hand ◽  
Vitro Binding ◽  
Dose Levels

Zearalenone (ZEA) is a potent estrogenic metabolite produced by some Fusarium species. No treatment has been successfully employed to get rid of the ZEA contained in foods. This study was conducted to evaluate the ability (adsorptive power) of five adsorbents—activated carbon, bentonite, talc, sandstone, and calcium sulfate—to trap ZEA in vitro. Activated carbon was the best adsorbent, binding 100% ZEA (pH 3 and 7.3) at 0.1, 0.25, 0.5, and 1% dose levels. Bentonite, talc, and calcium sulfate were less efficient than activated carbon but still could bind ZEA to some extent. On the other hand, sandstone was inactive in the experimental conditions employed. Our results indicate that activated carbon could be a good candidate for detoxification of ZEA present in foods.

Age and food hardness affect food handling by insectivorous bats

2007 ◽  
Vol 85 (9) ◽  
pp. 985-993 ◽  
Author(s):  
E.E. Fraser ◽  
M.B. Fenton
Keyword(s):  
Optimal Foraging ◽  
Feeding Behaviour ◽  
Eating Behaviour ◽  
Myotis Lucifugus ◽  
The Other ◽  
Food Handling ◽  
Insectivorous Bats ◽  
Male And Female ◽  
Food Items ◽  
And Gender

Eating behaviour can vary with age, experience, and gender, as well as food hardness. This variation can contribute to intraspecific dietary differences and may result in variable definitions of optimal foraging and decreased intraspecific competition. We quantified feeding behaviour of insectivorous bats eating hard and soft mealworm-based food items based on the bats’ ability to consume and manipulate food items, consumption time, chew frequency, and total chews to consume. Adult Myotis lucifugus (LeConte, 1831) were more successful at both consuming and manipulating mealworms and consumed mealworms more quickly, with greater chew frequency and in fewer chews, than did subadults. Adults chewed mealworm viscera more frequently than did subadults but showed no differences in the other variables. Adult Eptesicus fuscus (Beauvois, 1796) consumed mealworms more quickly and with fewer chews than did subadults but showed no differences in the other variables. There were no differences between adult and subadult E. fuscus when consuming mealworm viscera. Male and female M. lucifugus did not differ significantly when eating either mealworms or mealworm viscera. There was no change in subadult consumption time of mealworms over the summer. Age-based differences in eating abilities may play a role in defining optimal foraging and dietary composition in insectivorous bats.

The Effects of Adverse Environmental Conditions on Workload

1975 ◽  
Vol 19 (3) ◽  
pp. 301-304
Author(s):  
Ann E. Martin
Keyword(s):  
Environmental Conditions ◽  
Environmental Variables ◽  
Secondary Task ◽  
The Other ◽  
Random Numbers ◽  
Performance Decrement ◽  
Experimental Conditions ◽  
Continuous Noise ◽  
Adverse Environmental Conditions ◽  
Intermittent Noise

The present study was conducted to investigate the effects of environmental conditions on visual workload. The environmental variables used were temperature, studied at levels of 45°F., WBGT, and 95°F., WBGT; and noise, studied at 83 dBA intermittent noise and 93 dBA continuous noise. Workload was defined as the amount of attention demanded from an operator as measured by performance decrement on a secondary task while performing a primary and secondary task simultaneously. The secondary task was reading random numbers, and the primary task was reading word lists. Significant differences (p<.05) were found between the control condition and all experimental conditions. The low temperature and high temperature-continuous noise conditions were significantly different from the other conditions. Noise and temperature were found to significantly increase workload (p<05).

scholarly journals Perilaku Dan Musuh Alami Kupu Endemik Sulawesi Papilio blumei: Acuan dalam Konservasi

2015 ◽  
Vol 8 (1) ◽  
pp. 52 ◽  
Author(s):  
SULFIANTO ALIAS ◽  
RC HIDAYAT SOESILOHADI
Keyword(s):  
Life Table ◽  
Natural Enemies ◽  
National Park ◽  
Host Plants ◽  
Mating Strategies ◽  
The Other ◽  
Foraging Activity ◽  
Key Factors ◽  
Mortality Factors ◽  
K Value

<p class="5abstrak"><em>Papilio</em><em> blumei</em> is an endemic butterfly of Sulawesi and especially in Bantimurung Bulusaraung National Park. This research was to observed of the behaviour and natural enemies of <em>P. blumei</em> in Bantimurung Bulusaraung National Park. The behaviour of the insect were mating, foraging, competiting, ovipositing and mud-puddling. Life table was used for analysis of mortality factors, therefore the number of mortality was analyzed by key-factors formulation. The result indicated that mating strategies is patrolling. Foraging activity of the sixth instar was the highest compared to the other instars and the lowest one activity of the prapupa stadium of <em>P. blumei</em>. Nectar host plants for the imago of butterfly were <em>Sarcosephalum latifolius</em> and <em>Eugenia sp</em>. There was <em>Scudderia sp</em>. as an interspesific competitor for larval <em>P. blumei</em>. The intraspesific competitor of the imago stage was male of <em>P. blumei</em>. Female <em>P. blumei</em> laid eggs on abaxial leaf <em>E.hupehensis</em> and the eggs hatched after six days. The larva of  <em>P. blumei</em> has a overheating behaviour and the adults has a mud puddling. The natural enemies of <em>P.blumei </em>is <em>Trichogramma</em> sp., with k value = 0.381, <em>Pteromalus </em>sp., with k value = 0.125 and <em>Formica </em>sp., with k value = 0.096.</p>

Sign in / Sign up

Export Citation Format

Share Document