Fossils - Part 2: Orthoceras and Belemnites

Orthoceras (Phylum Mollusca, Class Cephalopoda) lived from the early Ordovician 495 million years ago) until the Triassic Period which ended 206 million years ago so the species was around for about 300 million years!

Orthoceras was carnivorous possibly even preying on trilobites and would have swum in the ocean or crawled on the sea floor. They ranged in size from a few inches to over 14 feet and their soft bodies lived in the last open-ended segment of their shell.

The name orthoceras means "straight horn".

It is the long conical shell that the animal lived in that is preserved as a fossil as can be seen in the photos of polished fossils below.








Belemnites lived during the Jurassic and Cretaceous Periods and were entirely marine being cephalopods that became extinct during the mass extinction event at the end of the Cretaceous 65 million years ago.

They looked very similar to today's squid and today their closest relatives are squid, cuttlefish and octopuses. It is believed they were carnivores and probably move through the water in a similar fashion to squid.

Very rarely whole belemnite fossils have been found but the vast majority are pieces of the bullet-shaped external skeleton which was made of calcite and called the guard (see photo below). The guard which was located at the rear of the animal may have acted as a counterbalance to the head at the front and helped keep the organism level in the water.

Belemnite fossils are often washed out of Jurassic and Cretaceous clays and occasionally large numbers occur together which may represent what was a mass mortality following mating, as happens with squid in current times.



Belemnites were name from the greek word belemnon meaning dart. During the medieval period it was believed that belemnites were thunderbolts which had been turned to stone.

Garden Update and (still) No Waxwings

I spent most of last Wednesday doing some jobs in the garden and planting up some pots for the winter and spring. Gosh, it was cold - I didn't thaw out 'till mid-evening. The flowers will provide a dash of colour in the winter and hopefully produce lots of blooms in the early spring providing nectar for any early emerging insects.

The tame robin kept me company enjoying insects and worms disturbed as I moved pots around. A grey heron flew low over the garden. We get occasional visits from herons - they usually land by the pond looking for fish and frogs. Not a lot else to report garden bird-wise just the usual species on the feeders although I did get a visit from a female chaffinch and I'm hoping chaffinch numbers will increase as winter progresses.









The Christmas tree,although still not looking 100%, is looking a lot healthier than this time last year when I thought I had lost it. My husband repotted it at the weekend.



I haven't put out the moth trap again either because the weather forecast has suggested a cold night or rain or I've been out in the evening. I have a feeling now that it won't get used again until next March unless we get a mild, dry spell.


I paid the Business Park a quick visit this morning - at least there were a few blackbirds feasting on the berries although not a fieldfare, redwing or waxwing in sight! There were the usual magpies and carrion crows around and highlight of the trip was a mute swan on the grass by one of the ornamental ponds.

Fossils - Part 1: Ammonites

I've been fascinated with fossils and the history of life on Earth for probably as long as I have been interested in natural history. Although my son went through the usual stage of being engrossed in dinosaurs and collecting fossils, its only in the last ten years or so that I have started to build up my own collection.

I find it absolutely amazing to be able to handle the remains of an organism that is millions of years old and its even more astounding when you find your own fossil and realise that you are the first person to have set eyes on the organism since it died all that time ago. Its estimated that between several hundred million and a few thousand million species have existed on Earth during the past 540 million years and of this number only a few hundred thousand species have been discovered as fossils. By comparison the number of species living today could range from between 5 million to 10 million species. The vast majority of species that have existed are now extinct.

Here's a selection of some of the ammonites from my collection




Ammonites which belong to the Phylum Mollusca and Class Cephalopoda were confined to the Mesozoic Era which included the Triassic, Jurassic and Cretaceous Periods (248 to 65 million years ago).

They were entirely marine and most were pelagic (living above the sea floor) and the majority were nektonic (active swimmers). It is thought many species were predatory feeding on plankton whilst others could have been scavengers. Ammonites ranged in size from 20 millimetres in diameter to well over 2 metres.

The ribs (and in some species spines and knobs) on the shell which can be seen on the photos below may have helped to strengthen it, provide protection against predators and may also have been used in sexual display.

The shell which was made of aragonite was a coiled tube which was divided into many chambers, the animal living in the outer open end of the shell. Chambers in the shell which had formed earlier would have been filled with gas and water acting as a buoyancy aid.

Ammonites were widely distributed throughout the oceans and evolved very quickly with each species having a fairly short life span and are therefore often used as zone or guide fossils to date Jurassic and Cretaceous sedimentary rocks.










Ammonites became extinct at the end of the Cretaceous 65 million years ago during the same mass extiction event that killed off the dinosaurs. Representatives of Cephalopods which survive today include squids, cuttlefish and octopuses. The nautilus is probably the nearest living relative to ammonites.

The following are photos of polished cross sections and in the first photo the frilled patterns are sutures which reveal where each individual chamber wall joined the inside wall of the coiled shell.








Sixteenth century natural history books mentioned similarities between the ammonite's coiled shell and snakes or serpents and ammonite fossils were once believed to be the petrified remains of snakes and were called "snakestones".Snakes heads were often carved on ammonites by fossil collectors at this time.

Fireworks and Fungi

I haven't had time to go out birding and there's not been a lot happening in the garden so I am going to be "scraping the barrel" a bit with this posting.

Blue and great tit and blackbird numbers are slowly increasing and I've witnessed two robins having a terriorial battle on several occasions recently. Still getting visits from a flock of long tailed tits that like foraging in the herbaceous border but have ignored the feeders. Two coal tits have been visiting the feeders and one is still hoarding sunflower hearts in one of the hanging baskets.

Although I was hoping to put out the moth trap at least one more time rain most nights has prevented this. In fact on the only dry night recently instead of putting out the trap we enjoyed some fireworks.










Finally, a photo of some fungi growing under the silver birches at the top of the garden.



I've been sorting through and photographing my fossil collection this afternoon and, as its going to be a busy week and I am not sure if I will have time to go out birding, the next blog posting is likely to be on ammonites!

A Successful Sparrowhawk

I glanced out of a house window this morning to see a male sparrowhawk on the lawn plucking a small bird. It stayed for several minutes before flying off with its prey held in its talons. I see a sparrowhawk in the garden several times a week but its rare to see it actually be successful in its hunting.

I did manage to get a photo - but please bear in mind this was taken through glass, at a distance of about 25/30 feet, with a 14-42 mm lens with flash and has been heavily cropped so its a very poor record shot!!




The rubbishy photo above has reminded me of a decision I need to make soon (my birthday and Christmas are rapidly approaching!!) concerning an addition to my photographic equipment. I really would like to be able to take some photos of birds and experiment with macro photography but my camera an olmpus e-420 digital slr does not have image stabilisation. I am, therefore trying to decide whether its worth spending several hundred pounds on an olympus 70 -300 mm zoom or possibly an 18-180 mm zoom or would lack of IS make these lens a waste of time. Alternatively, I could forget the zoom lens for now and buy a macro lens for insect, moth and butterfly photography.

I have also been looking at cameras such as the Panasonic Lumic FZ-45 or Fujifilm Finepix HS10 which seem to offer really good zoom lens and macro mode down to 1 cm. Would I be better buying one of these for possibly less money than just one olympus lens?

Decisions! Decisions! Any comments would be gratefully accepted.

A Fruitless Search for Waxwings!

I paid a brief visit to the Business Park this morning but there was not a sign of any waxwings - its really like looking for a needle in a haystack. Not even a consolation prize in the form of a fieldfare or redwing. The highlight of the trip was a trio of pied wagtails and there was a motley assortment of crows, wood pigeons and magpies. Even the ornamental lake was devoid of life - no sign of the 3 moorhens I saw the other day. Oh, well not to worry, it looks as though we are going to have a "waxwing winter" so plenty of time for more to enter the county.

There are zillions of berries and I am looking forward to further visits to see the species they will attract especially when the weather gets colder.

Missed Garden Tick

I came downstairs early this morning for a cup of tea and as I glanced up the garden I noticed an unusual bird in the border under the whitebeam. My first reaction was "what the heck is a snipe doing in my garden"! OMG its a snipe I thought! and turned to grab the bins. Well, of course in the time it took to walk a couple of paces and put the bins to my eyes the bird had disappeared. I dashed upstairs and got dressed as quickly as possible and tiptoed out into the garden. There was still no sign of the bird by the whitebeam or pond so I walked slowly up the garden and as I turned the corner of the path just behind the pond I spotted the bird at the same time as it saw me. Within that split second it had risen vertically and disappeared over the fence. The only identification features I had time to register were a cream stripe on the face and a brown and black streaky back.

As luck would have it I had promised to take my son to work and it was time to leave so I had to endure an hour return journey before I could look for the bird again. Despite continuously looking out of the windows all day and countless walks around the garden the bird hasn't returned - not that I really expected it to. Was it a snipe, jack snipe or woodcock grounded on passage migration? - unfortunately it doesn't look now as though I will ever know and I am hopping mad that I have missed what would have been a brilliant garden "first"!

I've watched countless snipe over the years, the odd jack snipe and a few woodcock but its very difficult when you see a bird in the garden (i.e. out of its usual habitat) and for just a few seconds (and when you are half asleep!) to gather the essential id features for a positive id - well it is for me any way. No doubt Bill Oddie would have known!

Garden Moths

After expecting an empty trap after putting out the moth trap Saturday evening I was really pleased to find 3 moths of two different species.

Feathered Thorn - this is a male and this photo shows the feathered antennae of the male really well.





I am pretty sure these two moths are the same species - Yellow-line Quaker - hope I have got the id right this time.





(All the photos have been quite heavily cropped)

Summary of Moths Caught - Saturday, 30th October

Actinic 15w Skinner Trap

6.00 p.m. until dawn

Minimum Temperature 8.7 degrees centigrade

1 x Feathered Thorn
2 x Yellow-line Quaker


I'll probably carry on trapping for a while as I'm still catching some moths.

Looking for waxwings

I went a quick drive out to the Business Park I mentioned last week - there are loads and loads of berries even more than usual. No sign of any waxwings or thrushes feeding on them but I will try and visit once a week to keep an eye on any feeding activity. I know waxwings have been seen at this site several years ago and last winter I saw a lot of fieldfares and redwings feasting on the berries.

Edit (at 20.45) - Have just visited a couple of local Warwickshire "sightings" blogs and, believe it or not, 21 waxwings were spotted today in the vicinity of "my" Business Park" - I will be returning there tomorrow!