Past Events

Petrified Forests of Zealandia

Petrified Forests of Zealandia. Speaker: Mathew Vanner, Department of Geology. This talk explores the history of Zealandia’s forest tree flora from a palaeontological perspective. Forests are our oldest and most persistent ecosystems and New Zealand, the Chathams and Auckland Islands have all yielded identifiable fossil wood from a range of ages and families. The fossils reveal an unbroken line of conifers, including Araucariaceae and Podocarpaceae, from the Jurassic (~170 Ma) to the Miocene (~10 Ma). New records of angiosperms, (Araliaceae, Myrtaceae, and Legumes), appear in the Eocene (~50 Ma) and other taxa (Casuarinaceae) disappear from New Zealand in the Miocene. Wood characters can be used to investigate palaeoclimate and show when key features developed in New Zealand lineages. My talk illustrates the exquisite preservation of fossil wood, the range of information that can be derived from wood features, and the history of many of the distinctive trees currently growing in New Zealand.

The ‘other half’ of New Zealand’s flora: how distinct are the non-native plants from the native?

Speaker: Dr. Angela Brandt, Ecologist, Manaaki Whenua – Landcare Research. Non-native species make up about half of New Zealand’s plant species, and those that have naturalised have added 68 families and 650 genera to the New Zealand flora. Non-native plants that are introduced and then naturalise are not a random subset of the global flora, but how distinct are these species from the native flora as a whole? I will give an overview of recent inventories of native and non-native plant species in New Zealand and the challenges involved in documenting the ever-changing composition and distribution of the ‘other half’ of New Zealand’s flora.

Weekend Field trip to the Hokonui Hills, Southland

Cancelled

Weekend Field trip to the Hokonui Hills, Southland. We plan to stay at the Dunsdale Recreation Reserve, which is near the township of Hedgehope southwest of Gore. The facilities are basic so you will need to bring a tent. You are responsible for providing your own food but plan to bring a meal for Saturday evening to share with the group. A track from the campground gives access to the Hokonui Forest where there is some interesting riparian forest along the Dunsdale Stream. Expect to see several species of orchid and some impressive specimens of the rare Coprosma, Coprosma wallii. Other places that we can visit are Forest Hill Scenic Reserve and Croydon Bush Scenic Reserve. We will leave Dunedin on Friday evening and return Sunday afternoon. If you wish to go on this trip please contact David Lyttle (03) 454 5470 email djl1yttle@gmail.com

A search for the co-evolutionary partner(s) of New Zealand’s sequestrate fungi

Speaker: Dr Toni Atkinson. New Zealand has long been known as a “land of birds”. The idea that the array of sequestrate fungi found here, many of which are colourful, may have arisen through coevolution with birds was first mooted in mycology around 20 years ago. It seemed a natural progression from the widely accepted hypothesis that New Zealand’s diverse divaricating plants evolved due to selective pressure from the now extinct moa species. The suggestion appears to have been taken up by mycologists, and is becoming part of the story of science in this land. Last year, an international team using high-throughput sequencing techniques to analyse the DNA in moa coprolites, revealed the first real evidence that moa may have eaten fungi. But what happens if we take a fresh look at the whole question? Are moa the most likely coevolutionary partners of our sequestrate fungi, out of all the vertebrate and invertebrate inhabitants of prehistoric New Zealand? In this recently humanised but greatly altered land, it is challenging to hold in mind the relationships that might have played out over evolutionary time. What might we have missed?

Trotters Gorge Exploration

If you are like me, then you’ve driven past the sign post for Trotters Gorge more times than you can count and thought “I really must stop one day for look”. So now is your chance! There are a couple of different environments we will explore, with tracks winding up through kanuka forest to the drier ridgelines and then down into broadleaf forest around the creek. For those who can look past the trees, there are caves (with weta potential) and sea views to be enjoyed. If you would like to come exploring, meet at Botany Department carpark at 9am.

Field trip to Karitane

Karitane is a site of both historical and natural significance, and much work is being done by Kāti Huirapa Rūnaka ki Puketeraki to restore the riparian and coastal habitat. Further details of the trip still to be confirmed. Meet at Botany Dept carpark at 9am.

Geoff Baylis lecture: Name changes among New Zealand ferns: the good, the bad, and the ugly?

Location: Castle 1 Lecture Theatre

Speaker: Leon Perrie

Taxonomists often claim they receive insufficient support for their task of describing the world’s biodiversity. But are they their own worst enemies? Their taxonomic outputs often attract the ire of their intended users because of the changes they prescribe to scientific names. We’ve still much to learn about the evolutionary history of life, so some taxonomic change is presumably allowable. But how much change is appropriate, and who decides? Fern and lycophyte taxonomy is currently in a particularly pronounced flux. For instance, the scheme prescribed by the international Pteridophyte Phylogeny Group would have New Zealand with no species of Blechnum, Cyathea, Lycopodiella, Lycopodium, and Trichomanes (changes to c. 20% of the local fern and lycophyte flora!). I’ll discuss my objections to this, given my personal opinion that it is important to minimise taxonomic changes while maintaining a taxonomy that still reflects evolutionary relationships (i.e., monophyly). I’ll include examples of new and renamed species, and lumped and split fern and lycophyte genera, alongside some relevant examples from among New Zealand’s flowering plants. You can decide what’s good, bad, or ugly.

Biography: Leon Perrie is a Curator of Botany at Museum of New Zealand Te Papa Tongarewa. His research is focused on the taxonomy and evolutionary history of New Zealand’s ferns and lycophytes, and he has co-authored over 100 peer-reviewed publications. A current priority is supporting the completion of the fern and lycophyte chapters for the electronic Flora of New Zealand. He also works with Pacific ferns, especially those of New Caledonia, and he occasionally dabbles with flowering plants (e.g., Pseudopanax, Schoenus, Sophora). He was the lead science curator for Te Papa’s recent revamp of its principal natural history exhibition: Te Taiao Nature.

Location: Castle 1, University of Otago (no drinks or nibbles due to covid)

Members night

Members are invited to bring items of botanical interest to the monthly meeting and talk about them. Items may be short slide shows, books, photographs, plants or any plant related object that has a story attached.

Field trip to Tavora Reserve, North Otago

Tavora is a coastal reserve near Palmerston managed by the Yellow-eyed Penguin Trust. Over more than 20 years the Trust has transformed the previously marram covered dunes into a showcase of pingao with many associated threatened species including shore spurge, Cooks scurvy grass and sand tussock. This is augmented with advanced riparian planting alongside the stream leading to the dunes. The reserve also has natural populations of the uncommon Aciphylla subflabellata, Lepidium tenuicaule, and Tupeia antarctica mistletoe hemi-parasitic on ribbonwood trees. We'll do an easy walking circuit of the reserve that takes in all the highlights. Meet at Botany Department carpark at 9am.

Silken harp chords and the green choir

Speaker: James Crofts-Bennett. The mutualistic relationship between the plant kingdom and the arachnid order Araneae is remarkable both in nature and how often it is over looked. There is extensive literary coverage on spider abundance and diversity in relation to vegetation texture diversity. So extensive is the research that beyond mere ecological significance, the relationship between spiders and plants has been adapted into agricultural practices! This talk will explore the theory, supporting evidence, then finally practical applications of exploiting this relationship. Research sites range from the William James building green roof to Orokonui ecosanctuary, grassy meadows to glorious podocarp forest and furtive fern villages! Descriptions of tiny tarsal claws guaranteed to make your skin crawl and close encounters with Aciphylla sure to incite sympathetic cringing! Come one, come all and behold the union of silken harp chords and the green choir!

Working morning at Orokonui Ecosanctuary

We will spend the morning leading a hand at the ecosanctuary, helping with a bit of weeding and seeing if we can add to their plant species list. In addition, there will be a chance to see the Otago Rare Plants garden (which many of our members have contributed to) and perhaps spy a takahe or tuatara. Meet at Botany Department carpark at 9am.

Sexy Lichens

Speaker: Dr Allison Knight, Research Associate, Department of Botany.

The lichen symbiosis is extraordinary, intertwining organisims from two or even 3 distantly related kingdoms. Lichenised fungi are extremophiles, capable of living in environments well beyond the range of vascular plants. Some can even survive days or years exposed to the vacuum, radiation and temperature extremes of outer space! Intriguingly, lichens are very sensitive indicators of air pollution and can also be useful indicators of climate change. On the lighter side, the Sexy Pavement Lichen grows on the asphalt outside the Botany Department, and covers footpaths and roads all over New Zealand. It has been exploited by the unscrupulous, enticed the gullible and recently caused a global media frenzy.

Fungal foray to Racemans Track

We will explore local fungi with a morning foray along Racemans Track. The track passes through areas of kānuka, which hosts ectomycorrhizal fungi, so it should be an interesting and valuable site to explore. Wear all-weather clothing, walking boots and bring cameras and morning tea. We will collect in the morning, and then those interested can return to the Department of Botany at lunch time to prepare the samples for drying and lodging in the herbarium. Bring lunch if you want to stay to process specimens in Botany. Meet at the Department of Botany car park at 8:30 am or at the Silverstream car park on Silverstream Valley Road at 8:45 am. Return at 12 noon.

BSO Annual General Meeting and Photographic Competition

The photographic competition is a popular and eagerly anticipated event for anyone interested in botanical photography. Enter your best photos and learn what makes a good photograph and how to improve your photographic skills from our panel of expert judges. Your photographs may be chosen for the BSO Calendar so this is your opportunity to have one month of fame. Start organising your entries now and don’t wait until the last minute.

A search for the co-evolutionary partner(s) of New Zealand’s sequestrate fungi

Speaker: Dr Toni Atkinson.

New Zealand has long been known as a “land of birds”. The idea that the array of sequestrate fungi found here, many of which are colourful, may have arisen through coevolution with birds was first mooted in mycology around 20 years ago. It seemed a natural progression from the widely accepted hypothesis that New Zealand’s diverse divaricating plants evolved due to selective pressure from the now extinct moa species. The suggestion appears to have been taken up by mycologists, and is becoming part of the story of science in this land. Last year, an international team using high-throughput sequencing techniques to analyse the DNA in moa coprolites, revealed the first real evidence that moa may have eaten fungi.

But what happens if we take a fresh look at the whole question? Are moa the most likely coevolutionary partners of our sequestrate fungi, out of all the vertebrate and invertebrate inhabitants of prehistoric New Zealand? In this recently humanised but greatly altered land, it is challenging to hold in mind the relationships that might have played out over evolutionary time. What might we have missed?