Saturday, 29 November 2014

Sharing a Home with Family, Friends and Strangers

Several animals share their homes with uninvited guests some of which give little trouble. Other invaders, however, may destroy the nest or kill the hosts.

Basket-weave hotel is the world’s biggest nest.

A haystack-like object hanging from a tree telegraph pole is a not uncommon sight in the dry grasslands or southwest Africa. It is in fact an enormous communal nest containing up to 300 woven grass baskets all clustered under one dome-shaped, thatched roof. It is the communal home of a colony of sociable weaver birds. The entrance holes are in the “basement” each one leading to a group of nests houses a pair of weavers and their brood, while in winter, it shelters a group of adults huddled together for warmth.

Sociable weaver birds somewhat resemble their close relatives, the European sparrows. They do not migrate, and even when they are not breeding, they occupy the same nests, coming home to sleep in them each evening after feeding on seeds and insects. The work of repairing and adding to the nest is constant, and the birds live for several. So though a colony may begin with only a small cluster of nests under a communally built thatched roof, in time the home tree’s strange fruit may grow into an enormous structure twice the height of a man and four times as long as it is high.

In a land where daytime temperatures are 34’C at night communal nesting is no bad idea. Inside the nests, the temperature fluctuation is halved by the insulation of the thatched roof and the woven sides. For security’s sake most birds’ nests tend to be inconspicuous. Not so the weaver birds, which can be seen from a great distance. These birds rely on safety in numbers and on the fact that few predators are able to reach the entrances without a warning being a called by at least one colonist. A problem lies, however, in the weaver birds own enthusiasm for buildings.

Busy Termites thwarted by Troublesome Tenants

Australian termite mounds are perhaps the pinnacle of insect architecture. Made from chewed plant matter and coasted with clay, these air-conditioned towers rise to about 23 feet high, containing within them innumerable chambers and galleries. Such conspicuous structures are bound to attract creatures that prefer to let someone else do the work of home building. One of the most determined idlers in the rare golden-shouldered parrot, found only in a small area of northeast Australia. In the breeding season, the female simply tunnels some 14 inches into the slab sides of a mound, hollows out a nesting chamber, lays her eggs and sits on them. She does not even try to seal the ends of the termite tunnels she has opened up. The termites do what they can to discourage the squatter, by working all night to seal its entrance hole. But to no avail. Each morning, the parrot breaks it open again. On rare occasions, the termites manage to entomb a clutch of chicks but the more usual outcome is that they give up, seal off their own tunnels and ignore the unwanted guests.

However, parrots do not always choose their termite mounds well. Magnetic or compass termites build their tall, blade shaped towers with the flat sides on a north south line so they get the most sun in the morning and afternoon and the least at midday. Because the tower thickness is less than 3 feet, golden-shouldered parrots that try to burrow into tone can easily find themselves jabbing at the air on the other side. Thus it is not uncommon to come across rows of magnetic termite mounds looking exactly like enormous, upended slices of Swiss cheese. At worst golden-shouldered parrots are no more than a nuisance. But termites also suffer from other tenants whose habits may kill a whole colony. They’re paradise, or whit-tailed, kingfishers. In early November, these lovely birds migrate from New Guniea to a little area on Australia’s North Eastern Coast.

There, mated pairs make nests in newly built termite mounds that are around knee high. An Australian golden-shouldered parrot perches on the huge termite mound it has claimed as its winter nesting place. Some older birds will return to the same cozy nesting site, year after year, blithely undoing the termites painstaking repair work. For the birds, the rain softened termite mounds are easy to excavate. The kingfishers create two narrow entrance holes by jabbing at the mound with their beaks. Then with their feet, they dig out the entire inner chamber for their eggs. The work can take up to a month, and in its course, inflicts more damage than a young termite colony can tolerate. The termites die or abandon the nest, leaving their unfinished home to the kingfishers and their chicks. Source: Charismatic Planet

Wednesday, 19 November 2014

Urchins with Spiny Umbrellas

Sea-urchins are not stationary creatures, but move around on shore and seabed using their spines and sucker like tube feet. Some can climb up vertical rocks, and even bore into them. Well, Sea-urchins belong to a group of marine animals aptly named echinoderms, meaning spiny-skinned. Starfish, brittle-stars, sea-cucumbers and feather-stars are also members of this group. Many of the sea-urchins around the British coastline live both above and below the low tide mark, either singly or in groups. 

Some species, such as the common sea-urchin, green sea-urchin and edible sea-urchin, live under stones, among seaweeds or in rock pools and crannies. But the heart-urchin, or sea potato as it is commonly called, burrows in sandy shores. Although the living creatures are often hidden from view, you may often find the round, hollow and colorful shells of dead sea-urchin washed up along the strandline. 

Spiny test, the shell tests look like an external skeleton. But for the living urchin it is also an internal one, covered in a thin layer of living tissue which contains the digestive and reproductive organs. The test is made up of layers of white limy plates. As the animal grows, it adds more layers each year with layers of pigment in between. You can tell the age of a sea-urchin by counting the numbers of layers. The edible sea-urchin for example, can live for 8 years or more. The edible sea-urchin (Echinus esculentus) is found on rocks and among seaweeds along the English Channel and Western coasts, from the low tide mark to a distance. As with other sea-urchin its mouth is armed with a set of five sharp teeth operated by a structure called Aristotle’s lantern named after the Greek philosopher who first described the animal in detail, the Aristotle’s lantern may be found intact inside empty tests. The cut away contains the gut rising from the center and coiling inside. Five yellow sex organs are visible, and are edible hence its name. The test is normally 10cm (4 inches) in diameter and when empty and cleaned is a beautiful mixture of reds and purples, with small white knobs where the spines about 1.5cm long were attached. The spines which cover the test an soon break off when the animal dies not only protect the sea urchin against predators, but also help it to feed and to move about. In some species, the spines enable the animal to burrow into sand or bore into rock. 
On the move Sea-urchins also have a number of tube-feet interspersed among the spines, which they use chiefly for movement and also for respiration and waste disposal. The tube feet make p part of a complex structure known as the water vascular system. Sea-urchins pump fluid through their bodies to help them move about. The fluid, largely sea water is pushed through a series of tubes to the tube-feet which then extend. The sucker-like tip of a tube foot grips firmly once it touches a rock or other firm surface. The muscular wall of the foot then contracts, and the water is forced back through the canal system. As the foot shortens, the animal is pulled along. Once attached to a rock, Sea-urchins are difficult to dislodge. 

The tube-feet project through holes in the Sea-urchins test, in a characteristic pattern of five double rows running from top to bottom round the body. You can clearly see the tube-feet holes on empty, spine free tests. The Sea-urchins mouth and teeth are on the underside of its body. The edible Sea-urchins and other rocky shore species, move slowly over the rocks to graze on the vegetation especially soft young seaweeds. 

Colorful Varieties

Sea-urchins common around the British Isles vary in size from five to fifteen cm their shapes differ from rounded to heart shaped, and the colors alter dramatically from black to bright purple and to the pea green of the green Sea-urchins. The common Sea-urchins sometimes called the rock-urchin, forms groups in or among rocks between the high and low tide marks. If it cannot find a rock pool or suitable cranny, this urchin makes its own shelter against the waves, wind and sun by boring into the rock. Its teeth bore deep into the rock, while the spines widen the hole. The much larger edible Sea-urchins live down on rocky shores. It is only uncovered at spring tides, when the low water mark reaches its lowest point; but the slightly conical  empty test may be found higher up the beach. The tests are a colorful reddish brown and are often sold as souvenirs. 
Sea Potato

This Sea-urchin is also known as the heart-urchin because of its fragile heart shaped test. It differs from other Sea-urchins in that it lives in burrows on sandy shores near the low tide level. Like many animals in this habitat, the sea potato burrows to find somewhere to live and to exploit its food source in the sand, as well as protecting itself against the drying effects of the sun and wind, or the force of the waves. 

A group of spines on the underside near the mouth which are longer and spoon-shaped are specifically for digging down into the sand. A star-shaped depression on the surface shows where a heart-urchin has recently burrowed. Once underground it feeds with the use of special tube-feet and collects and grains from the burrow floor. Spines around the mouth then scrape off the food particles. 


Like several animals, Sea-urchins do not mate but shed their eggs and sperm into the sea (groups of sea potatoes gather together to help ensure the maximum numbers of eggs are fertilized). Spawning takes place in spring and the fertilized eggs develop into minute rounded larvae, with four arms that stick out and up. The larvae float among the plankton, later settling on the seabed to transform into adults.


The green sea-urchin if often found under stones or seaweed on the parts of the shore that are covered by the tide lower shore. Green Sea-urchins (Psammechinus miliaris) greenish test up to 4cm across violet spines 15mm long. 

Monday, 10 November 2014

Percy Harvin traded to New York Jets for conditional draft pick, per report

The New York Jets have acquired receiver/returner Percy Harvin from the Seattle Seahawks for a conditional draft pick, according to Jay Glazer of FOX Sports. Harvin has been injury-prone throughout his career but has played in all five of Seattle's games this season.

For the Seahawks, this move is stunning. Seattle has designs on becoming the first team to repeat as Super Bowl champions since the 2004 New England Patriots, and it just traded one of its best playmakers for a future pick. Harvin has 133 receiving yards, ranking third on the team, but has also added 283 return and 92 rushing yards so far.

The trade ends the Harvin era in Seattle, which saw him play in a total of six regular season games and two postseason games over two years. Harvin had a big impact in the Super Bowl, scoring on a kickoff return to begin the second half.

To acquire Harvin before the 2013 season, general manager John Schneider dealt first- and seventh-round picks to the Minnesota Vikings along with a third-round selection in 2014. Schneider received a conditional pick in return from the Jets, making this move a net loss in terms of draft picks and money.

iOS 8.1 Problems Frustrating iPhone Users

While the iOS 8.1 releases brings fixes for several iOS 8 problems, it appears that the update has delivered some new problems of its own as iPhone and iPad users are struggling with assorted iOS 8.1 problems just a day after the update’s arrival. In late September, just a few weeks after iOS 8.0 came out of the beta program, Apple released iOS 8.1 beta. Apple did not attach a public iOS 8.1 release date to the beta leaving consumers wondering when the update would arrive. iPhone and iPad users had put great importance on iOS 8.1 release due to a number of iOS 8.0 issues and iOS 8.0.2 issues on board Apple’s iOS 8 update.

Last week, Apple announced a public iOS 8.1 release date, confirming the update for Monday, October 20th. Yesterday, as promised, Apple released the iOS 8.1 update for the iPhone, iPad and iPod touch. The update, as expected is a sizable update that not only includes support for Apple Pay but comes packed with an assortment of tweaks and changes that are meant to improve Apple’s new iOS 8 update.

As we have discovered, the iOS 8.1 update’s fixes do tackle some of the iOS 8 problems that plagued iPhone and iPad users for several weeks. The iOS 8.1 update eradicated an issue wherein the iPhone would get stuck in landscape mode and it also squashed an iOS 8 bug that caused read iMessages to be labeled as unread. We’ve taken a deep dive into the iOS 8.1 update and while our experiences have been mostly positive, it looks like the update has delivered iOS 8.1 problems to iPhone and iPad users.

iPhone and iPad users on iOS 8.1 are reporting a number of iOS 8.1 problems that appear to be affecting the overall performance of their device. Apple’s discussion forums are flooded with complaints about the new iOS 8.1 update and problems range from installation issues to Bluetooth issues to random freezes and slow down. Numerous iPhone and iPad users are complaining about assorted installation issues that have prevented them from getting the iOS 8.1 update installed on their device. These issues are different than the server issues that we encountered in the minutes after the iOS 8.1 release yesterday. iPhone and iPad users say that their installations have stopped abruptly during the process. Fortunately, there is a fix for these issues, one that we relayed yesterday.

Unfortunately, many of the iOS 8.1 issues being reported don’t have permanent cure-all fixes. iPhone 5s users are reporting random reboots after iOS 8.1. An iPhone 5 user told us that his iMessages stopped sending immediately after installing the iOS 8.1 update. We’re also hearing about Wi-Fi issues including Wi-Fi speeds seemingly being throttled on the iPhone 5s and iPhone 6 and erratic connection speeds. Those’re just the tip of the iceberg.

iOS 8.1 users also say that they aren’t able to move their mail into the trash, assorted Apple Pay problems, Bluetooth issues, Airdrop issues, problems with iOS 8.1’s hotspot feature, random stability issues in Safari, Bluetooth issues in the car, issues opening files in Mail, Spotlight suggestion problems, and a whole lot more.

Specific of those aforementioned threads contain temporary fixes, several of them do not. And while we do not have fixes for all of these issues, we do have some fixes for some of the most common iOS 8 problems found on the iPhone and iPad. These fixes apply to iOS 8.0, iOS 8.0.2 and they also should work for iPhone and iPad users that
are running the iOS 8.1 update. For now, iPhone and iPad users will need to rely on these unofficial fixes for answers to their iOS 8 problems. Apple hasn’t announced any new iOS 8 updates and it hasn’t dropped any new updates inside its beta program.

We haven’t seen any iOS 8.1.1 pickup in our analytics either which suggests that a release isn’t imminent. We’re going to continue to dig into Apple’s latest update over the next week as iOS 8.1 problems remain to emerge. Apple’s rumored to have two new iOS 8 updates up its sleeve for 2015 including an iOS 8.2 update and an iOS 8.3 update. Neither update has made an official appearance nor does it be still not clear what will be next for iPhone and iPad users running iOS 8.1.

Friday, 7 November 2014

Pollen and Pollination

Pollen is the dust, usually yellow in color, produced by the stamens and made up of millions of microscopic granules, the shape size and appearance of which are characteristic to the individual species. Each granule is responsible for the production of male sexual cells, the gametes. In order for the gametes to be conveyed to their female counterparts, contained in the ovules, the pollen granule must come into contact with the stigma. This is the process known as pollination and it represents the most critical moment in the life of a flower. Although the outcome of this process is strongly conditioned by chane, nevertheless evolution has effectively reduced the accidental element by fostering certain mechanisms that guarantee, at least statistically, the success of pollination. The oldest and most widespread of such mechanisms involve insects which as carriers of pollen travel from stamen to stigma and from flower to flower. The flower reciprocates by putting food substances, namely nectar, a source of carbohydrates and pollen itself, a source of protein at the disposal of those insects. The plant in fact is well equipped to produce a surplus of pollen so that a part of it can be used for fertilization. 

There’s a wide range of specialization between flowers and insects. In some flowers the nectar is stored at the end of a long, narrow coralline tube for example, the Cape leadwort, Plumbago auriculata, visited by insects with a very long mouth apparatus, such as butterflies, some of these tropical flowers such as the family Bignoniaceae are pollinated by the tiny hummingbirds. Often the arrangement of the flower’s internal organs is such as to compel the insect to become smeared with pollen in order to reach its food; when the insect visits another flower are pollinated by insects and among these so called entomophilous flowers are the zygomorphic forms. But there’re numerous species in some cases entire families, which are Anemophilous, i.e. pollinated by the wind. They’re characterized by many inflorescences, sometimes soft and pendulous (Catkins or amenta) of numerous small flowers, almost or wholly lacking a perianth and so structured and inclined as to expose their anthers and stigmas to the slightest breath of wind. Anemophilous flowers obviously produce and expend a much greater quantity of pollen than entomophilous flowers because their type of pollination is that much more uncertain. The success rate is highest in dry, windy climates. These’re also flowers such as those of Fallopia baldschuanica of the Polygonaceae which are both entomophilous and Anemophilous, capable of being pollinated by both methods. 

Once the pollen reaches the stigma, the sticky, sugary liquid that covers its surface attracts the pollen granules and induces them to germinate. Within a short time each granule then protrudes a pollen tube, which lengthens to grow through the style, digesting and feeding on its internal tissues. Continuing its growth, the tube reaches the ovary and eventually, the ovule. Meanwhile the embryo sac a group of a few cells, two of which are the female gametes has formed inside the ovule. When the pollen tube comes into contact with the embryo sac, fertilization proper takes places. The tube releases into the sac two male gametes which unite with their female counterparts to produce, respectively the zygote i.e. the first embryonic cell of new seedling and the initial cell of the endosperm, the nutritive tissue of the seed plant, the function of which is to feed the new plant during its early stages when it is incapable of carrying gout photosynthesis. In some seeds this food tissue does not form and in such cases initial nutrition is accomplished by the first leaves of the seedling itself, those already formed in its embryo, the cotyledons.