#Advent Botany Day 23: Vanilla – nothing plain about this flavour! — Herbology Manchester

I’m not one for cream on my Christmas pudding, it just has to be custard or ice cream and so what I’m really admitting to is a love for vanilla. Vanilla is the quietest spice at Christmas but there is so much more to vanilla than merely two scoops of icecream. Natural vanilla is the fruit […]

via #Advent Botany Day 23: Vanilla – nothing plain about this flavour! — Herbology Manchester

Collaborated with Rachel Webster and Sophie Mogg on this piece about the history of vanilla.

Cuckoo Logic: The Alien World of the Brood Parasite

The cuckoo is at the emotional heart of evolutionary biology. Whilst puzzles such as altruistic behaviour and the peacock’s tail can be solved by a tweaking of evolutionary theory and a realigning of our image of nature; the behaviour of the European cuckoo, Cuculus canorus, is different. The cuckoo’s behaviour cannot be dressed up with human ideals of the family and morality. In the figure of the brood parasite, we see the bones of natural selection lain bare, naked and unavoidable.

A cuckoo egg mimicking the two reed warbler eggs in a reed warbler nest

The behaviour of the female cuckoo contradicts cultural ideas about what parenting, particularly mothering, is. There is no concept of parental love for the cuckoo; the mother will slip into the nest of the selected host, pluck out a host’s egg, quickly deposit her own egg and leave. She pays no part in nurturing the offspring; she is the proverbial bad mother. But the more paternal aspect of parenting is also absent in cuckoos. Most human cultures value parents passing down the knowledge and values they accumulate in addition to their genetic material to their children. Familial traditions have no meaning for the cuckoo, for it receives nothing from it’s parents except their gametes and the home range they return to in the breeding season.

The cuckoo hatchling comes of age in an environment very different from our bustling human world. They are fed by their hosts, each subspecies or gentes of cuckoo is host species- specific, and are unlikely to see any other cuckoos before they fledge. Despite this, by adulthood they must have an idea that only European cuckoos, not the host species, are sexual partners. The cuckoo chick must on some level know that the creature caring for them is not ‘their kind’, one of the first things they must do is understand themselves as a stranger.

A cuckoo chick ejecting reed warbler eggs

When the cuckoo chick hatches, sightless in a nest full of host eggs, it behaves in a way chilling to see, a puppet governed by pure evolutionary logic. Like a murderous sleepwalker, the naked red cuckoo will hoist the hosts’ eggs (or hatchlings) into a hollow of its back, shuffle to the edge of the nest and discard the hosts’ progeny, to die outside the nest. This grisly scene is repeated until all rivals are gone. It is left lord of the nest, and can enjoy the food the hosts brings unhindered. We may recoil from the cuckoo chick and it’s “odious instinct”, horrified by a babe whose first action is sin. But this exemplifies the error of applying human morals to all animals indiscriminately. They were never innocent so cannot fall from grace – they just act out a strategy honed by their ancestors.

See a short, if sentimental, video of this here.

Illustration by Laura Cooper of a cuckoo chick being fed by a reed warbler host

What baffles most about the cuckoo’s world is the behaviour of the host. Here “host” refers to the parasitic relationship between the cuckoo who exploits the resources of the unrelated pair who raise it, just as I may be the host exploited by Plasmodium in malaria. But the case of the cuckoo suggests a different meaning of “host”. The host pair appear to welcome the cuckoo chick; they are passive as it ejects their offspring and feed it even as it grows to monstrous sizes. The sight of a reed warbler contorting itself to ram an insect down the throat of a cuckoo twice its size suggests a relationship that has passed hospitality and become subservient.

This can lead us to see the host as either foolish or manipulated by the Machiavellian chick. Both of these descriptions are partially true. But the host is only temporarily foolish. In evolutionary time the species will become wise and the cuckoo will lose the evolutionary arms race and move onto a naive host species. The blackbird still has vestiges of its victory over the cuckoos, its chicks will eject strange eggs from the nest though cuckoos must have long given up parasitising this species.

The cuckoo chick does manipulate – it’s calls mimic a whole brood of the hosts’ chicks to trick the hosts to give it enough food to fill several host chick bellies. But as Nick Davies in the book Cuckoo: cheating by nature suggests, manipulation by the chick is not the sole reason for hosts’ care. Davies reports that reed warbler parents will accept odd chicks of many other species, it is not due to the skills of the cuckoo. It is instead due to the breeding patterns of the host itself.

The reed warblers have evolved great skill at recognizing cuckoos attempting to parasitise nests and rejecting cuckoo eggs. This is because at this stage there is still a significant chance they can have another brood before they migrate. But once a given pair has had a cuckoo hatch in the nest, it is too late to have another brood before they migrate, and only a 50% chance of making it to the next breeding season. Therefore, the hosts carry on as if they had their own offspring, as they can do nothing now to increase their reproductive success.

It is likely that it would benefit the host pair to reject cuckoo chicks and save the energy spent caring for them on preparing for the next breeding season. But this strategy cannot evolve. The low probability that a cuckoo-rejecting pair will ever breed means that the genes associated with this behaviour can’t pass to the next generation and so meet an evolutionary dead end.

Instead of the foolishness or manipulation, what is really seen when the reed warbler feeds the stranger in its nest is something that exists because of an absence of positive or negative selection pressures, as selection cannot touch it. The reed warbler responds to the cuckoo chick by replicating the behaviour it uses to feed its offspring as no counter-strike against the cuckoo can be evolved.

Adult male cuckoo

The “Deep Otherness” of Plants: On Hope Jahren’s Lab Girl


I’ve spent much of the time since reading Hope Jahren’s memoir Lab Girl in November pressing the book into the palms of anyone whom asks for recommendations. This is not because it is something tritely described as a science book which non-scientists can enjoy, as if this means it has been specially dumbed down. This book is not concerned with explaining scientific concepts about how the world works, which won’t attract a person not interested in thinking in causal mechanisms. Jahren is not concerned with detailed explanations of her work, instead the book starts prior to this and explores what draws us to look at the world with a curious mind, a thing we all inevitably do whatever our day job. It is more impressionist than explanatory, with the tautness and rhythm of literature, dealing with what drives a particular sort of person cram themselves into small lightless rooms with big questions and anxious hearts.

Lab Girl is Jahren’s autobiography of becoming and painfully establishing herself as a scientist. She works at the intersections of many disciplines and  could be described as a plant geochemist, one of the few scientists who spend their time sifting and sorting data extracted from rock samples to constructing landscapes millions of years gone. I enjoyed this spotlight on an under-hyped branch of science whose way of looking at the living world we all should learn from. Jahren and her colleagues see with the panorama of the palaeontologist and the eye of the environmental scientist for the interplay of living and non-living and so understand the environment as ever shifting, the present world should not be taken for granted.

Jahren structures chapters about her life and work around short vignettes about how plants live. Though she writes of the “deep otherness” of plants, plant scientists do find that the organisms so often on their mind inevitably colours their experience of their own lives. The perils and the struggles of life as a plant mirrors Jahren’s as a scientist, a woman and a person with bipolar disorder. For instance, a chapter on the curious S-shaped growth curves of corn which suggests the traumatic process of making seed is followed by a chapter detailing Jahren’s pregnancy; the emotional turbulence of going off medication in the first two trimesters and in the final trimester being formally barred from her lab as a “liability”. This juxtaposition is more than metaphor. What Lab Girl does best is to convey what it is like to think like a scientist, to have your mind percolated by your subject matter and methods until you yourself become entwined within it.

This is not to say Lab Girl is a romantic account. There are numerous horror stories about funding struggles, scrabbling enough money to pay the salary of Bill, her career long collaborator who spent much of the early days sleeping in the lab or his car. Bill is Jahren’s colleague, but they act more like siblings than two professional.They spend blissful nights in the lab constructing experiments and defrosting hamburgers, pepped up on a steady stream of dark humour. Rather pleasingly, both Bill and the many Mass Spectrometers Jahren has had in her life appear far more frequently than her husband. But Jahren does not dismiss family life, a scene towards the end of the books sees her refer to the two halves of her heart, both full when she puts her son to bed and goes off to the lab to put the half given over to science to use. She doesn’t see either side of her life as detracting from the other, they are all components of what she is.

Jahren does not make her bipolar disorder explicit for the first part of the book, no doubt mirroring its emergence in her life,though this did mean it took me a while to realise that her long hours and nocturnal lab habits are not typical, and shouldn’t be purposefully emulated. I’m cautious around first person account of bipolar disorder as they can be interpreted as glamourising mania and making it desirable for people who don’t have bipolar, which it ultimately never is. Thankful, Jahren avoids this.

On the flip side, except for her pregnancy, her bipolar or the stigma associated with it does not seem to have subtracted from her career significantly. I suspect however that Jahren was of the first generation to do so in significant number, as they would be doubly perceived as irrational and unscientific for being mentally ill and women. Jahren discusses the sexism she has faced, and locates its burden to the “the cumulative weight of constantly being told that you can’t possibly be who you are”, the knee-jerk assumption of what a scientist can be which affects more or less all but the white European, wealthy middle-aged able-bodied man.

Whilst the title suggests the book’s subject is the “girl”, I think Jahren intended the stress to be on the “lab” in which the girl happens to be in. Jahren grew up in her father’s lab, and sees the labs she has built over the world as her home, a refuge from the outside world where she can be herself. The book is a love letter to the physical and mental space to think, play and discover that a lab of one’s own brings to the female scientist in particular.

Lab Girl is not a The Double Helix style account of one extraordinary discovery, Jahren sees science as work and herself as “like an ant, driven to find and carry single dead needles [..] and then add them one by one to a pile so massive that I can only fully imagine one small corner of it”. Whilst a science appears to be progressing in leaps and bounds from the outside, as seen from the individual point of view science stagnant with your budget or regresses as your work is made irrelevant.Whiggish narratives are irrelevant or dangerous on a day to day basis, so Jahren explores the pleasure of her work itself; to try to understand the logic of plants, from the inside. But the moments of discovery are beautiful when they happen, such as the blissful moment when Jahren is standing in the lab in the sunrise thinking herself the only one in the world with a newly discovered gem of knowledge, making her “unique existentially”.

As a young woman with designs on making a (increasingly circuitous) route into research science, I have absorb Lab Girl not as a manual for being a scientist, but rather as a suggestion of a way of being as a scientist, a path already flattening down the grass. A path which shows the principle is possible, but does not dictate the route. But it is more important to me as a showing how a life scientist can draw upon their subject – these strange ways of being as a way to reflect upon your own life, to use the subjectivity of another as a way to root yourself in the chaotic seas of your own subjectivity.

The Poison Chronicles Festive edition: Poisoner and matchmaker – the joys of mistletoe — Herbology Manchester

Guest blog by: Laura Cooper Whilst many species of plants are referred to as mistletoe, the icon of Christmas is the European Mistletoe Viscum album. Mistletoe has a varied reputation; it is a symbol of Christmas and druidic ritual, a poisoner and a matchmaker. The plant itself belongs to the Santalacea or sandalwood family. It […]

via The Poison Chronicles Festive edition: Poisoner and matchmaker – the joys of mistletoe — Herbology Manchester

I’ve started writing a series on poisonous plants on the blog of the Manchester Museum Herbarium, this edition is about the many facets of mistletoe; symbol, poison and drug.