(posted in Evolution)


Yes, humans (Homo sapiens) are evolved from a group of apes (the Homininae), which shared a common ancester with an ape species that was also the forerunner of modern chimpanzees, somewhere around 7-8 million years ago. Further back (maybe 9-10 million years ago), this common ancestor of what would become human-like apes and chimpanzees evolved from another ape ancestor, one branch of which went off to become gorillas. Further back still, the common ancestor of what would become gorillas, chimps and humans had anotehr branch that became orangutans an so on back.

This is obviously a very simplistic description of the main speciation events, there is plenty of good information out there: https://en.wikipedia.org/wiki/Human_evolution; http://www.britannica.com/science/human-evolution etc. but these again give a digested version. To truly understand human evolution, there are a number of excellent textbooks and journal articles that would be useful for you to read but the above will at least give you a start understanding the basic events and the processes of speciation.

(posted in Plants & Fungi)

Hi Christina,

This looks like Sequoiadendron giganteum, apparently there are some in Tasmania: https://en.wikipedia.org/wiki/Sequoiadendron_giganteum

Hi Sarah,

If you're in the UK or Europe, I woud say that this is Vespa crabro, the European hornet. There are other species of hornet around the world (and some are moving into Europe and the UK!), so without knowing more about where you are or seeing the abdomen clearly, it is difficult to say for sure.

Hi Kat,

The photos you have are definitely a leech.

I'm not a leech expert, by any stretch of the imagination but there are a couple of points I can make:
1. This leech is harmless to humans - only the very rare medicinal leech and the horse leech can penetrate human skin; other leech species are parasites of fish and other aquatic vertebrates
2. Leeches in th UK live in both still and flowing waters; without further information on the potential hydrological regimes where you live, it is difficult to say how and why these little critters are getting into the house. It may be worthwhile getting the drains checked to ensure they are not blocked.

I hope this helps a little.

Hi Laura,

Great questions! My understanding (happy to be corrected by those that have experienced this!) is that, unfortunately, the very 'basis' of humanness (a large brain relative to body mass, influencing sociality, consciousness etc.) is a harsh compromise between that large brain and the ability to stand and walk upright (which frees the upper limbs for more complex actions and grants other 'benefits') .

The large brain is likely to have been a result of a confluence of an increase in higher protein in the diet (meat intake - moving from vegetarian to omnivore diet) and an increase in dexterity (tool use).

It is likely that as early hominids moved from an arboreal existence to a bipedal existence, due to a drying climate between 5-7 million years ago (mya) in the East African Rift Valley, there were a variety of environmental pressures that selected for increases in bipedality, leading to knock on effects in subsistence utilisation and foraging (maybe dietary or foraging changes) and then, possibly, tool usage. There doesn't appear to be too many large scale morphological changes from the early hominids, such as Ororin at c. 5.5mya, through the gracile Australopithicines to the early Homo species, where an increase in tool use and meat consumption (Homo rudolfensis, perhaps at c. 1.8mya!?) started a positive feedback loop of increasing brain size.

As brain sizes increase for our distant ancestors, there is an increased limitation on the ability of the female pelvic girdle (which has changed shape and size from that of our ancestor to accommodate upright walking) to pass the skull of the child, until such a point is reached that there is a definitive limit to what the female human can feasibly pass through the pelvic girdle, which is, essentially, where we are now.

The benefits of bipedality (in evolutionary terms), as well as the benefits of a larger brain (and all the complexity that comes with that!) are the trade off with the pain of childbirth (and the very real threat of death that many women have (and still do in places) had to face before the advent of modern medicine). So, no flaw, just a compromise! Had we maintained a more quadrapedal stance, then childbirth would have been 'easier' i.e. more comparable with our primate relatives but without the 'benefits' of bipedality and large brains, which make us what we are.

The dependency of our children is again a compromise between our large brains and the amount of development that can be undertaken within the womb before the skull becomes too large to be passed through the pelvic girdle. 'Ideally', human children would be gestated for longer than 9 months within the female to make them more capable at birth but the skull would be so huge it simply wouldn't be able to be born!

Maternal instinct and bonding is common to all primates but is, perhaps, more highly developed within humans as our offspring are, relatively, more helpless than our common relatives (chimpanzees and gorillas) at the same age.

I hope this very quick skip through human evolution provides some answers but it is, obviously, only an incredibly brief and incomplete elucidation on the complexities of human childbirth. If you have specific questions based on the above, please don't hesitate to ask and we'll do our best to answer them

Depending on where you are, this certainly looks like a hornet Vespa crabro and the behaviour sounds like that of the hornet. Again, it looks like a hornet but without a better picture and / or more information, perhaps hard to be definitive.


Without a high quality photo, we are probably going to struggle for a species ID; see if you can get one and upload it to the site.



(posted in Human Biology and Evolution)

Does this help? http://en.wikipedia.org/wiki/Corticotro … te_peptide

If you have a more specific question, please post again.

The basal thorax is covered by the wings, so can't tell if it is 'waisted' or not but the length of the  antennae make me think perhaps more of an ichneumonid wasp... More information wouldn't hurt, like locale in the world and location of sighting...


This is the caterpillar of the elephant hawkmoth Deilephila elpenor. They feed, naturally, on bedstraws Galium species but like to feed on fuschias in gardens. When threatened, the larvae retract their head which protects this area but also inflates the body and enhances the eye spots just behind the head: http://www.uksafari.com/jpeg3/elephant33.jpg

Yes, absolutely, there are many, many different species of earthworm that all operate in different ways (feeding method, soil depth, soil moisture, soil texture etc.), so I'd be surprised if your earthworm struggled!


Yes, the earthworm would have been fine. For small creatures with a low mass, dropping from almost any height is unlikely to do much damage, as impact with the ground (Force) equals mass x acceleration (F=ma). As gravitational acceleration on the earth is a constant 9.81 metres per second per second, you can see that for a large mass (a person or a horse, for instance) dropped from anything more than about 2m is going to generate a large force, which will usually involve at least broken limbs. 20m and a human or horse is going to splat, where as an earthworm would happily crawl away...

(posted in Evolution)

Hi Brend,

This made me smile!: 'My initial thought was to write a paper on "Are we still evolving?" but found this subject too broad and I'd like to focus on paleoanthropology.' Because paleaoanthro is such a *small* subject!

I have no idea at what level an EPQ is or how long it is supposed to be. Is it degree level? Lower than a degree? Masters level?

Admittedly, it is a good while since I did human evolution for my undergrad but you need to think about what are you interested in.

You could look at work on the human genome if you're interested in genetics and relatedness; preservation and taphonomy of fossils if you're interested in the bones, geochronology, dietary isotope information, the rise of symbolism, lithic cultures, inferences in sociality etc. etc. etc. The list is endless!

I guess getting an idea from your teacher / tutor / lecturer would also be productive as to the kind of questions they are expecting you to answer.

Once you've had a think and talked to your teacher and if you wish to discuss a specific idea in more depth, please post again. As it is, the question is a bit too broad for us to help you much more than what I've provided above.

If southern France, almost certainly Macroglossum stellatarum.


You'll be fine to remove the nest. The adult wasps (workers) will have died or in the last throws of their seasonal life. The next queen will build a new nest next year.

My money would be on slug or snail eggs, these are not like  any spider eggs I've ever seen.

I think it is possible but probably unlikely.

It appears that the less derived features (including protruding claws, assumed weak flight and inability to echolocate) of Onchonycteris finneyi were apparent at about 52.5mya. Confusing the picture is the presence of Icaronycteris index at around 52.2mya that could echolocate but showed other, less derived features than modern bats.

These species are the closest we currently have for 'protobats' and I doubt that their heritage as what we would define as bats heads back another 13 million years or so to the Cretaceous.


Although diificult to tell fully from the angle, this is likely to be the giant woodwasp Uroceras gigas. It is absolutely harmless to people (just like 99.9% of all native UK fauna!) and uses the 'sting' in the tail to lay eggs in wood.

Sounds like the movement of a leech but not much to go on there, I'm afraid!


Without knowing where you are in the world or the size of this critter, very difficult to say for sure. Based on the photo you have supplied, I would say that this is a member of the Hemiptera, a group of insects with partly membranous wings and include froghoppers, leaf hoppers and shield bugs (here in the UK).

Yep, definitely a male golden-ringed dragonfly. A species of moors and heaths, they like shallow streams on these habitats with gravelly or silty bottoms that the females lays her eggs in. The nymphs can live for 3 to 5 years, depending on temperature and prey availability.


This is a female scorpion fly of the genus Panorpa. There are 3 species in the UK but can only be correctly identified by looking at the genitals.

Nice shot!

Without a very good photo, we are unlikely to be able to give a species name from your description but you might be noticing 'sea gooseberries' http://www.beachconnection.net/news/goo … 11_338.php (Cnetophora jellyfish)...

I'm afraid that the photos aren't quite clear enough but I suspect it might be (depending on where you are in the wordl!) something like a wasp beetle Clytus arietis...

(posted in Evolution)

This has been answered before: http://www.askabiologist.org.uk/answers … hp?id=7599

In short, you don't. You need to have a fully developed adult to say definitively whether a spider is male or female. Only adult females have fully developed epigynes and only adults males have fully developed 'boxing glove' like pedipalps. Studying the structures of these is very important in accurately identifying spiders to species level.

I'm in the UK, so I have no idea! However, I would suggest it is probably the larva of a beetle (possibly a South American Carbid??), as in the UK some beetle larvae (Carabids in particular) are mobile hunters.

It could, however, be the adult form of a beetle that looks like a larvae (so here, the female glow-worm (a beetle), for instance, looks far more like the larval stage than she does the adult male).

I'm afraid I can't help further; I wonder if any of our other (more widely travelled) contributors have an idea?

(posted in Birds)

The addition of grit / small stones etc. to a bird's food settle in the gizzard, which are then used to help soften and crush food.  Numerous extant and extinct species have used small stones etc. in this way; they are known as gastroliths: http://en.wikipedia.org/wiki/Gastrolith


No, they are definitely not thrips but I can't make out what they are! Best guess is that they are the nymphs of a Hemipteran bug but I can't be sure from the photos that you've uploaded; sorry!

No, neither cockroaches or mantids have two brains.

Both groups (the Mantidae and the Blattodea) belong to the superorder Dictyoptera, so they are more related to each other than any is to any other group: http://en.wikipedia.org/wiki/Mantis. As such, they will share a number of characteristics (that could be physical or genetic) that group them into the superorder Dictyoptera that excludes other groups of insects...


This is a female hornet hoverfly Volucella zonaria: http://www.askabiologist.org.uk/answers … p?id=11170

Without knowing anything of the American fauna for 'glow-worms' (which may or may not be related to European 'glow-worms'), I would speculate that the most likely reason is habitat change or habitat loss (most of the declines in abundance and / or range for species we have good data for tend to be habitat specialists). Modifying, even subtly, an organisms habitat can dramatically effect the chances of breeding, mating or even surviving to adulthood. In the UK, our 'glow-worm' (Lampyris noctiluca) is a beetle, predominantly of hard limestone / chalk grasslands, where there are plentiful numbers of small snails for the larvae to feed on. The loss of these grasslands in terms of absolute size, linkage and quality are reasoned to explain, at least in part, the possible decline of this species (and many other, more surveyed species, like moths and butterflies).

There are, obviously, many other possible explanations that may work independently or in conjunction with the above (these things are usually a combination of fectors that are complex to unravel) but as I don't know anything about the species to which you refer, its life history or the region, I'm afraid that I can't speculate much further.

And another! http://www.askabiologist.org.uk/answers … p?id=11170

Another V.zonaria: http://www.askabiologist.org.uk/answers … p?id=11170

Yep, female Volucella zonaria. More info here: http://www.hoverfly.org.uk/viewtopic.php?t=45

Hi Kelly,

I'm afraid that I can't discern any features that would help me identify this thing. Can you get a better (macro) photo? Otherwise, I think we're going to struggle! Where are you in the world?

I would say that you are likely to have a female hornet hoverfly Volucella zonaria. The females have a bright yellow band separating the eyes, which is what *seems* to be shown on your photo.



I do not know the fauna of Greece but I would suggest that the second critter is Malachius bipustulatus or a similar species.

No idea about the first one though, some kind of hornet mimic or a wasp species I'm completely unaware of??


I'm afarid I can't tell from your photos exactly what you have.

However, cow parsley has now gone over, so anything with flowers is almost certainly not cow parsley. Cow parsley has green, hollow, unmottled, hairless stems.

There are a couple of very similar later season successors to cow parsly, the most common being rough chervil. This has solid purpled blotched stems but is rather coursely hairy.

Hemlock has a hairless, purple-blotched stem and looks generally 'unpleasant'. However, looking at your Picture 1, the leaves do not look fine enough to me but they could be.

Picture 2 could be rough chervil but it looks like the stem is hairless and you don't mention hairs.

Picture 3 looks more like cow parsley...

I would suggest investing in a good plant field guide if you want to properly identify plants in your area, the Collins guide is pretty good; the Francis Rose field guide is also very good but perhaps a touch more expensive...


I would suggest this is probably Hemaris thysbe (or a closely related species, as I'm not familiar with the Canadian moth fauna!); a member of the Macroglossinae, the hummingbird hawkmoths. It might be worthwhile asking a member of staff of your local museum or (if it exists), a local moth recorder (or maybe even an expert at a state or national museum) for full identification, as they will be more familiar witht he species in your area.

Boxelder looks pretty good Al!

Hi Candy,

I don't know the American fauna at all but this is a hemipteran bug (i.e. an insect with piercing mouthparts and 'different wings' - a hard and membranous area to the modified forewings, the 'hemelytra'), not a fly at all.

Other than that though, I really don't know enough about the species you have in the States to get to a species. Sorry!

Hi Debra,

There is a sum total of one arachnologist for this site and I don't know how well he knows the USA spider fauna, so the chances of an identification to species level, particularly without a detailed photo, are probably pretty slim, I'm afraid!

However, he might just pull something out of the bag! ...

It is obviously a beetle of some description. Where are you in the world? It looks bloated, so may well be a gravid (pregnant) female. It appears as though there is some kind of ovipositor, although I don't know of any beetles in the UK that have this appendage. Alternatively, it could be the aedeagus of the male but again, the bloating doesn't seem to fit with this.

Not sure. More information or more photos may be really useful...

Hi Paula,

This is the larva of a Harlequin ladybird; you can record your sighting here: http://www.harlequin-survey.org/

In short, it wasn't a millipede! Millipedes are not quick critters. You almost certainly saw a centipede (perhaps one of the larger stone centipedes Lithobia)...

As with (most!) spiders, Ricardo, they display fully adult sexual morphology. In male wolf spiders (Lycosidae), this takes the form of enlarged distal (end) segments to their pedipalps (like little boxing gloves just in front of the mouth: http://www.spiders.us/files/spider-geni … oscope.jpg) and for the female, she has a fully formed epigynum (http://www.spiders.us/files/female-spiders-epigynum.jpg). These act, partly, as 'lock-and-key' mechanisms to prevent / reduce cross-breeding.

Obviously, a number of spiders are sufficiently closely related to produce viable hybrid offspring but in the main, these physical characteristics (plus other behavioural cues) prevent too much cross-breeding: http://www.bioone.org/doi/abs/10.1111/j … 07.00146.x

Without a detailed photo of the eyes or spinerets, I can't say for sure. Most likely it is a Scotophaeus blackwalli or closely related species, due to the silky fur-like covering to the abdomen.

I'm afraid I don't have recourse to my textbooks at the moment but it depends on which species, their location and food availability. I would suggest about 6-8 instars until adult form is reached...