Origami or flower? With a dahlia captured in black and white it can be hard to tell the difference. Is the presence of the spider (which looks like Dendrolycosa putiana, an inhabitant of south and southeast Asia) enough to tell you that it is a true flower seen in a garden? Or are you still undecided?
Tag: spider
Honey trap
When you go for a walk on a wooded hillside in autumn you should expect to see that many of the plants have gone to seed. This is so even if the hill is called Phulchowki, which means a custom house of flowers. Perhaps especially so. But this is a good time to notice something that you the profusion of colour of a month earlier may have hidden. Every flowering plant is an invitation to pollinators to come and help it have sex. The honey pot under the flower’s sexual organs is the payoff for the pollinator. But the cone of the flower is often also a trap for the creature. Spiders lie in wait inside the cone.
In the featured photo you can see a flower is wilting away, its job done. But a hopeful spider still lurks in its debris, with its feelers strung across the collapsing mass. The mchanics of the hunt are now laid bare: it hides high up under the sexual organs, to jump down on its prey as it burrows down for the honey pot. The hillside was the realm of jumping spiders, as you can see from the numerous tripwires spread among the plants. Which means that in the right season there will be spiderhunters here: many species of those tiny birds with long curves beaks which can grab a spider even if it retreats deep inside a flower. The web of nutrition spread wider than we could see: from under our feet where the fallen leaves were rotting away, to the sky above.
Arthropoda
Spiders, beetles, millipedes, for sure. Moths? Maybe. Butterflies, like the lemon pansy (Junonia lemonias) in the photo above? A stretch. Crabs and lobsters. Certainly not; that’s food! Have we reached the limits of the folk classification of visible bugs? Consider. Spiders are perhaps more closely related to horseshoe crabs than to beetles. And if you think sea lice are bugs, then their close relatives, the shrimps shouldn’t be exempted. So let me go with arthropods instead: those invertebrates with an exoskeleton and jointed legs and segmented bodies. (Ands are powerful things, easily lifting fifty times their weight in sentences. After all we have jointed limbs, and segmented vertebrae. But we are not arthropods, because we are not invertebrates.) I’ll go with this, because it gives me a reason to finally read two papers (this and this) that I’d been meaning to for a while.
When did arthropods come into being? Darwin noted an uncertainty: “For instance, I cannot doubt that all the Silurian trilobites have descended from some one crustacean, which must have lived long before the Silurian age, and which probably differed greatly from any known animal.” Darwin’s intuition has been vindicated by the discovery of new fossils which pushed the origins of arthropods beyond the Silurian period (445-420 million years ago) into the Cambrian (535-490 million years ago). I took this photo of a fossil arthropod, a trilobite, in Shanghai’s Museum of Natural History. That bug was the size of my hand! The species, Sinoptychoparia tuberculata, is known from this single specimen from 515 million years ago, preserved in a sheet of stone from China’s Guizhao province. The oldest fossils of arthropods that we know of are not more than about 550 million years old, embedded in the proliferation of animal forms that is called the Cambrian explosion. This roughly agrees with genetic information.
Of all the forms of living beings known and recorded, arthropods are the most varied. But the living species of arthropods are just a small fraction of all their extinct cousins. All of today’s arthropods are either crustaceans, insects, myriapods (millipedes, centipedes and their relatives), or chelicerates (spiders, hermit crabs, and related species). But there are many groups of animals which seem to be closely related: tardigrades (which recently failed to colonize the moon) and velvet worms certainly, but also roundworms. In Darwin’s time it was expected that arthropods must have evolved from the much older group of roundworms, the annelids. The biggest discovery since Darwin’s days is that genome analysis shows that arthropods do not come from annelids. I think that is my biggest take-away from the first paper. These genomic studies have completely rearranged the branches of the tree of life around arthropods into a form that Darwin would not have suspected.
Insects evolved from cave-dwelling crustaceans about 480 million years ago, late in the Cambrian period (that’s the headline of the second paper). Beetles began to develop about a 130 million years later. They have had time to evolve into a variety of shapes. So many, in fact, that J.B.S. Haldane remarked that “If one could conclude as to the nature of the Creator from a study of creation it would appear that God has an inordinate fondness for stars and beetles.” All insects have a pair of antennae to smell with, but the one I saw on the beetle on the wall outside my flat was really spectacular. This photo was taken in October 2019, and I saw another specimen in November 2022. So, whatever it is (help me if you can, as the Beatles implored), it is not uncommon. There are many ideas, but no certainty yet, about how antennae developed.
If you wander through the fossil section of a museum, you are likely to see insect fossils similar to today’s lacewings and dragonflies. All have two pairs of wings like modern insects. The earliest known fossils of winged insects are a little more than 300 million years old, but genomic studies now show that insect flight arose about 400 million years ago. So, one should expect fossil hunters to discover even older specimens. I’ve written earlier about how a butterfly is grounded by a predator taking a bite from its forewings, but it can continue to fly with reduced manoeuvrability even after losing large parts of its hindwings. Flies seem to have only one pair of wings, because the hindwings are reduced to small appendages called halteres. They lose control over their flight paths if the halteres are lost. Beetles have converted one pair of wings into a hard cover, and still retain an ability to fly. I wonder whether dragonflies and damselflies can also keep aloft without using their hindwings.
Ants are fascinating. With the wonderful cameras that many of us carry in our pockets, I’ve been looking at ants in detail for some years now, without being able to identify them. These have elegant striped bodies which were quite hard to see at first because of the lack of contrast with the flower they are clambering over. When we think of pollinators, ants are not the first to pop into our heads. We think first of bees and butterflies. Interestingly, both these families have their origins before the rise of the flowering plants. Their spectacular diversity, however, comes with the explosion of flowers about a 140 million years ago. Ants also date from that time.
The origins of spiders and related groups of animals still remains to be understood fully. Early ancestors of today’s spiders are visible in the fossil record in the middle Cambrian. Animals that we would perhaps recognize as spiders may have lived about 400 million years ago. They have had time to evolve into the many lifestyles we recognize today: the orb weavers, the jumpers, or the ambush hunting crab spiders, like the one in the photo above. Arthropods are an old order of animals, filling a variety of niches across the world. Even insects are much older than flowering plants. So tales of the insect apocalypse are overblown. If we heat our world beyond our limits, we might carry some arthropods into extinction with us (lobster claws could become rare), but far from all.
Intersections
Farmlands may look tame to you, but seen in the small it is as wild as the jungles. The farmers around Chhoti Haldwani had planted pumpkin vines to grow over the Lantana that takes over berms. They were in flower. I love that bright yellow, a colour that remains even after you batterfry them. I haven’t eaten the flowers in years, because you don’t get them in markets in Mumbai. I remembered the taste as I took this photo of an ant crawling down in search of nectar. There were also a few tiny moths sitting on the flower. If I’d had the time to stand there, I could have got photos of a very large variety of insects as they came to it in search of food.
You can see more of these intersections of different kinds of life if you walk through the fields. Like this blade of grass, converted into a trap by one of the fiercest carnivores of this tiny world. Some spiders can eat around 10% of their body weight in a day. This web has a couple of spidery snack wrapped up for later. The trap is as indiscriminate as a fishing trawler’s net, and has snagged some dandelion seeds. I wonder whether the spider comes along later and cuts them loose.
A small and dangerous world
We spent a couple of nights last week in an extremely wet part of the Sahyadris. I’d expected the room to be full of mosquitos. It wasn’t. I discovered why only when I turned my macro lens on the lovely brick wall that the architect had designed. It was meant to be a substrate on which moss would grow. Indeed it does. But my camera caught more than moss, as you can see. The canyons between the bricks were walls of silk.
Mosquitos, and other insects were decimated by the microscopic predators which live in the environment that we have built for them. My macro lens barely caught a glimpse of the spiders; they are less than a millimeter across (you can barely see it in the photo above). I won’t find it listed in a field guide. If I want to identify it I will have to catch an expert. I wonder where they used to live before humans began to build an ecology specially for them. We worry so much about feral dogs and the loss of cheetahs. We have no idea what havoc we play on the ecology at these sub-millimeter scales.
Round the web
I stop at this spot in the garden once a day. I’m sure to see some butterflies here at any time. Yesterday I saw this strange spider web. A spider web has radial threads which aren’t sticky; these are the first threads that the spider lays down to make sure that the web will be stable. Once these anchors are in place, it moves crosswise along them laying down the sticky spiral thread. If you look carefully, you can see the fine lines of this spider’s radial and spiral architecture in the featured photo. But the spider was doing something weird here. While it moved spirally along the web, it seemed to lay down a much thicker spiral.
I haven’t seen anything like this before. I read later that when a spider wishes to move, sometimes she eats up the old web. Could she have been doing that? Maybe she lays down something to soften the thread before eating it? Videos on YouTube (a great reference site for the amateur naturalist) show that the dismantling of a web is very straightforward; the spider doesn’t have to season the silk before eating it. Nor was this the process of wrapping prey in silk. Could it be an invader trying to attack the original inhabitant? As I watched, I saw only one thing moving. I cursed myself for not carrying a magnifying lens with me. I went back again today to look. The web had disappeared. Maybe it was an invasion that I had seen.
Slugs and snails and puppy dogs’ tails
Walking through Kandawgyi gardens
The sprawling 425 acres of the Kandawgyi botanical garden is one of the best places to spend your time in the British era hill station called Pyin Oo Lwin. It was founded by the British Army colonel May and called Maymyo (May’s town). The summer capital of Raj-era Burma remained one of the favourite spots of army generals, so the town has been kept manicured and clean, but renamed. We saw amazing things here: a Hoolock Gibbon in the open (featured photo) and Takins (a Himalayan goat-antelope). Everything we saw here could also be seen in India, but you’ll have to travel to the wilds, and be lucky, to see them.
A meandering walk through a garden is a quiet and peaceful way to spend your time, so look through the photos below at your leisure, without my chatter to break the peace.
Don't hold your breath 
