The Flying Saucer At Sunset

Lenticular clouds (Altocumulus lenticularis) are stationary lens-shaped clouds with a smooth layered appearance that form in the troposphere, usually above mountain ranges. One was spotted in Singapore recently...

Eyes Of 30,000 Honeycombs

With 30,000 individual facets, dragonflies have the most number of facets among insects. Each facet, or ommatidia, creates its own image, and the dragonfly brain has eight pairs of descending visual neurons to compile those thousands of images into one picture...

A Kaleidoscope Of Colours, Shapes And Patterns

Spectacular and innovative in design, the Flower Dome replicates the cool-dry climate of Mediterranean regions like South Africa, California and parts of Spain and Italy. Home to a collection of plants from deserts all over the world, it showcases the adaptations of plants to arid environments...

Lightning Strikes, Not Once, But Many Times

Unlike light, lightning does not travel in a straight line. Instead, it has many branches. These other branches flashed at the same time as the main strike. The branches are actually the step leaders that were connected to the leader that made it to its target...

Are You My Dinner Tonight?

A T-Rex has 24-26 teeth on its upper jaw and 24 more on its lower jaw. Juveniles have small, sharp blade-shaped teeth to cut flesh, whereas adults have huge, blunt, rounded teeth for crushing bones. Is the T-Rex a bone-crushing scavenger?

Jurong Lake - Sunny Side Up

11:26 AM  , , , ,  

Jurong Lake
West, Singapore
February 2015

One of final finds of the day was this narcissistic Ardea cinerea (Grey Heron) at the edge of the pond sunning.


Sunning, usually a solitary practice, is where birds deliberately expose themselves to sunlight as opposed to merely being out in the sun. Spread-wing postures may serve different purposes in different species. 

Species that spend much of their lives in the open, such as waterfowl and shorebirds, are constantly exposed to the sun. For these species that have little chance for respite from the sun it may be that what we think of as sunning is actually the birds trying to cool down by exposing their feathers.

Some waterbirds have feathers whose structure are not water-repellent, but instead absorb water to decrease buoyancy and facilitate the underwater pursuit of fishes. They also lose body heat tin the underwater chase process. The function of the spread-wing postures in these birds is then to dry the wings, and to thermo-regulate to warm back their bodies. While they will take advantage of full sunlight, these birds need to dry out after every diving session so they are compelled to hang their feathers out to dry regardless of whether the sun is shining.

Cormorants, in contrast, apparently use spread-wing postures only for drying their wings and not for thermo-regulation. They stand with their wings open to keep themselves warm on a cold day and to warm the food in their belly to assist with digestion. The Marabou Storks on cool mornings also turn their backs to the sun and open their wings to warm up. The Black Heron and other birds that feed in shallow water often form umbrellas with their wings. By spreading their wings, they form a shadow so that they can see into the water better. Fish will come to hide in this sheltered "protected" area, and then become easy prey.

Other species spread their wings in the sun to realign their feathers, to force parasites into motion to ease their removal, and to help themselves balance on a perch.


So which one is your reason, Mr Heron?

Sources


"Questions my Grandkids asked me: Why do birds spread their wings when they stand?" (23-Jun-2014) by Johan Smulders from HubPages at http://johansmulders.hubpages.com/hub/Why-do-birds-spread-their-wings-when-they-stand.

"Spread-Wing Postures" (1988) by Paul R. Ehrlich, David S. Dobkin, and Darryl Wheye at https://web.stanford.edu/group/stanfordbirds/text/essays/Spread-Wing_Postures.html.

"Sunny Side Up" (06-Mar-2013) by Jill Brown from Australian Birdlife at http://birdlife.org.au/australian-birdlife/detail/sunny-side-up.




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Marang Trail - The Magic Of Spiders At Night

3:02 PM  , , , , , , ,  

Marang Trail
South, Singapore
February 2015

Ant Mimicking Spiders (Myrmarachne)


This Myrmarachne Spider avoids being eaten by predators by appearing like an ant rather than a spider. This defense is two-way: Ants are not as palatable as spiders to most general predators, and spider-specialized predators might not recognize these spiders as food.


For mimicry to work optimally, though, spiders must inhabit places with plenty of ants. Not the easiest task, since ants eat spiders. And the poor vision of ants helps. Because these ant-mimicking spiders do not smell like spiders, nor do they smell like ants. In fact, they do no smell like anything at all - They are stealth spiders!

Another one spotted hiding in a curved leaf strung together by its web - See the intricate outlay of threads just to hold the leaf together?
 

Pale Spitting Spider (Scytodes pallida)

The Pale Spitting Spider (Scytodes pallida) has a unique habit of spitting a glue-like and possibly toxic substance at its prey to render them immobile prior to envenomation. Behavioural studies demonstrate that the spider regulates its spit expenditure when offered prey of variable sizes and struggling intensities. 


Moving about on a plant with leaves devoured by grasshoppers into artistic patches, this Sac Spider spreads its long legs over the gaps to balance itself...
 

Though it is produced in venom glands in the chelicerae, the fluid contains both venom and spider silk in liquid form. The venom-impregnated silk not only immobilizes prey such as Silverfish by tying it down, but has a venomous effect as well. In high-speed moving pictures, the spiders can be observed swaying from side to side as they "spit", catching the prey in a crisscrossed "Z" pattern. It is crisscrossed because each of the chelicerae emits half of the pattern. The spider usually strikes from a distance of 10–20 mm and the whole attack sequence is over in a little under 1/700th of a second. After making the capture, the spider will typically bite the prey with venomous effect, and wrap it in the normal spider fashion with silk from the spinnerets.

  

Orb Weavers (Araneidae)

The typical orb-weaver spiders (family Araneidae) are the most common group of builders of spiral wheel-shaped webs often found in gardens, fields and forests. Their common name is taken from the round shape of this typical web, and the taxon was formerly also referred to as the Orbiculariae. However, orb-webs are also produced by members of other families.




Orb-weaving spiders make their webs at night time and usually take them down in the morning. They eat the silk, leaving only the base line to rebuild on. Constructing the web uses a lot of the spider's energy due to the large amount of protein required, in the form of silk and after a time the silk will lose its stickiness and becomes inefficient at capturing prey. Eating their web is a way for the spider to recoup some of the energy used in spinning. The silk proteins are thus "recycled".

An orb-weaver with some web debris and an egg pod on its web...


An  Argiope versicolor (Multi-coloured St Andrew's Cross Spider) flexing itself on its web without its trademark "X"...

A male Argyrodes flavescens (Red Silver Spider) on its own web for once...

Comb-Footed Spiders (Theridiid) are entelegyne (have a genital plate in the female) araneomorph ecribellate (use sticky capture silk instead of woolly silk) spiders that often build tangle space webs and have a comb of serrated bristles (setae) on the tarsus of the fourth leg.

The large golden orb-weavers (Nephilidae) and the long-jawed orb weavers (Tetragnathidae) were formerly included in the Araneidae; they are indeed closely related to them, being part of superfamily Araneoidea. Their webs are similar to those of the typical orb-weavers, but tend to be less sophisticated and often have an irregular instead of a neat spiral arrangement of the prey-capturing threads.


Members of the species Tetragnatha are stick-like spiders with long legs and well-developed jaws. They build delicate orb-webs with open hubs. The webs are suspended horizontally or in an inclined plane. The male jaws are particularly elongated and are equipped with a spur each. These are instrumental in locking the jaws of the female during mating.


Like many species of the superfamily Araneoidea, Nephila Spiders have striped legs specialized for weaving (where their tips point inward, rather than outward as is the case with many wandering spiders). Their contrast of dark brown/black and green/yellow allows warning and repelling of potential predators to whom their venom might be of little danger.

A Nephila Spider with its freshly-caught dinner...

Golden orb-weavers reach sizes of 4.8–5.1 cm (1.5–2 in) in females, not including legspan, with males being usually 2/3 smaller (less than 2.5 cm, 1 in). They are also the oldest surviving genus of spiders, with a fossilized specimen known from 165 million years ago.

The intricate layout of colours with patches, stripes and spots...

Neoscona punctigera (Ghost Spider)

The last time that Merlion Wayfarer spotted this was in 2012, among the long grass in Punggol. At that time, it was evening, and the spider was dormant. (See "Ghost Spider - Happy Halloween!")

(File Photo)

This time round, it was refreshing to note how active it is at night. Awaken from its daytime slumber, this Ghost Spider was moving about. With its flexible joints, one gets the impression that it is sorting out how not to stumble over its own legs.


Waving its long legs about to increase the perception of its body size - A sign of aggression... 


Sources

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Marang Trail - The Dragonheads

7:55 PM  , , , , , , , , , ,  

Marang Trail
South, Singapore
February 2015

Blue-Spotted Tiger Beetle (Cicindela aurulenta)

Tiger beetles are a large group of beetles known for their aggressive predatory habits and running speed. They have large bulging eyes, long, slender legs and large curved mandibles. All are predatory, both as adults and as larvae. Both Cicindela and Tetracha are often brightly colored, while the other genera mentioned are usually uniform black in color.


The fastest can sprint at up to 5 miles per hour, covering 120 of its body lengths in a single second. For comparison, Usain Bolt covers just 5 body lengths per second. To match the beetle, he’d have to run at 480 miles per hour.


Tiger beetles use this incredible speed to run down both prey and mates. But as they sprint, their environment becomes a blur because their eyes simply can’t gather enough light to form an image. They have extremely sharp vision for insects, but when they’re running, the world smears into a featureless smudge. To compensate, the beetle has to stop to spot its prey again, before resuming the chase.


After reading about how active they are at night, and how fast they can run... It does make it a "miracle" that this little one was stationary on this plant for the entire duration that Merlion Wayfarer was there at the Trail - First when she entered the Trail, and 3 hours later when she left the Trail...

Termites (Blattodea)

Instead of swarms of ants, the dampness of night allowed thousands of big-headed termites to roam around. Unlike ants, they don't bite. But not careful, and you will step into a swarm...

Slugs & Snails (Gastropoda)

This is a snail...

These are slugs...

These slugs look remarkably like snails without shells...

Snails and slugs are both part of the same class of creatures called gastropods. Gastropod comes from the Greek words gastros (stomach) and podos (foot). If you’ve ever seen a snail in an aquarium eating as it moves slowly along the glass, you probably understand why “stomach foot” is an appropriate name.

The most obvious difference between snails and slugs is the fact that snails have shells. A snail’s shell is like a home it carries around on its back. Slugs, on the other hand, have no shell. 

Snails and slugs make mucous so that they can move on the ground. The mucus keeps their bodies from losing moisture to the dry soil beneath them. It also protects them from being cut by sharp objects in the soil.

Hirudinea (Leech)

It is always creepy to see these slimy creatures. Looking like a black earthworm,
it slithers along from crevice to crevice...

What makes it a leech? 

Leeches differ from the oligochaetes (other worms) in significant ways. For example, leeches do not have bristles and the external segmentation of their bodies does not correspond with the internal segmentation of their organs. Their bodies are much more solid as the spaces in their coelom (main body cavity in a multi-cellular animals) are dense with connective tissues. They also have two suckers, one at each end.


As a point of interest, leeches are hermaphrodites, meaning each has both female and male reproductive organs (ovaries and testes, respectively). Leeches reproduce by reciprocal fertilization, and sperm transfer occurs during copulation. Similar to the earthworms, leeches also use a clitellum (a thickened glandular and non-segmented section of the body wall near the head) to hold their eggs and secrete the cocoon.

Caterpillars (Lepidoptera)

Tussock Moth caterpillars are known for their striking tufts of hair, or tussocks. Many species exhibit four characteristic clumps of bristles on their backs, giving them the appearance of a toothbrush. Some have longer pairs of tufts near the head and rear. Judged by looks alone, these fuzzy caterpillars seem harmless yet many people are allergic to the body hair of tussock moth caterpillars, especially if the hairs are brought into contact with eyes or sensitive areas of skin.

Tussock Moth adults are often dull brown or white. Females are usually flightless, and neither males or females feed as adults. They focus on mating and laying eggs, dying within days.


The beautiful cat here with dew on its spikes after the afternoon rainfall...

More caterpillars with those long "harmless-looking" bristles...

This is probably a pupa...

This is probably how an adult looks like...


Cockroaches (Blattodea)

In the dark of the night, these jungle roaches appear. Looking similar yet different to the cockroaches we often see at home...

If one each is not enough, there can always be two...

Whatever Are They?

These yet-to-be-identified Insecta were spotted too...

A hard-to-capture shiny black beetle against a dark background and an easier subject on a green leaf...

The Katydid (Tettigoniidae) with its beautiful lined eyes...

This is a beautiful albino Planthopper (Fulgoroidea) with beady red eyes and coconut husk-like tufts...

The Dragonheads

This is a 3rd instar Elymnias hypermnestra agina (Common Palmfly) Butterfly Caterpillar with its still blackish Masked Rider look. It will mature into a simple brown butterfly adult which is shade-loving, and usually sighted flying along the edge of vegetated area and in the vicinity of a clump of palm trees. The Palmfly adults have the habit of puddling and visiting flowers for mineral and energy intakes....


This stunning Polyura hebe plautus (Plain Nawab) Butterfly Caterpillar with its elaborate "headdress" will grow into an elegant beauty with a large, pale silvery-green median patch on each brown wing. At the 5th instar lasts for 10-13 days, this caterpillar can grow up to a body length of 48-50mm. Toward the end of this instar, the body gradually shortens in length. The fully grown caterpillar soon abandons its "base camp" and goes in hunt for a pupation site.



Sources

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