They’re here! 🥳 Very excited to welcome #PhD students from IPB PKSPL IPB ~ funded by our Biodiversity Challenge Funds project on incentive-based approaches in SSFs ~ on a 2-week exchange visit to Oxford Biology MCEM Oxford 🇮🇩🇬🇧🦈💙

The IUCN Red List is a critical indicator of the health of the world’s #biodiversity . 🦈 🐢 🐅

Learn about how it works, who uses it and more bit.ly/3eOFoe5 @IUCN

Scientists Discover Ancient Ghost Shark In The Depths Of The Andaman Sea

“The discovery of new species like this chimaera tells us how little we know about the marine environment and how much is still to be explored,' says Dr. David Ebert.

buff.ly/3X7hxuk

The third reason to celebrate the ocean is the incredible biodiversity cradled in its waters.
From the first life form that formed in our oceans over 4 billion years ago, to the 200 000 identified species today, the life in the ocean is rich beyond measure.

The personally tragic story of the act that probably resulted in the greatest number of documented extinctions. For 25 other conservation videos see youtube.com/@Bill_Sutherla…

From reef sharks to deep sea sharks, giant whale sharks to tiny dwarf lantern sharks, iconic great whites to less-famed tasseled wobbegongs, #sharks exemplify the extraordinary evolution of our ocean over millions of years. 🦈

Share your favorite shark & why! ⬇️

📸:SergeUWPhoto

Australian Whipray (Himantura australis) added to the Shark and Ray Database:
sharksandrays.com/australian-whi…

Congrats Brittany Heath on your final Honours presentation!

If you ever wonder if you could leave incisions unsutured when deploying acoustic tag internally, ask Britt!

We've been concerned at the lack of focus on #nature and #biodiversity in the UK's political discourse, given how important and urgent an issue it is. So we wrote to all the leaders and environment spokespeople in political parties contesting the election theconversation.com/the-uks-nature…

Nicholas Dulvy Wade VanderWright 🌊🦈 - Ecological lifestyle and gill slit height across sharks - Royal Society Publishing
royalsocietypublishing.org/doi/10.1098/rs…

A remaining challenge is to further refine estimates of maternal investment, especially between yolk-sac live bearing and histotrophy which may represent a gradient in terms of energetic input rather than discrete characters.

This study highlights a potential key difference between sharks and teleosts: a slower rate of the evolution of reproductive isolation in sharks, suggesting different rate limiting steps to diversification between these two groups. Interesting roles of polyandry and hybridization

Overall diversification rate increases from egg-laying to live bearing (1.5 times) and from live bearing to matrotrophy (1.3 times), and is 2.5 times higher in matrotrophs than egg-layers.

While teleosts have demonstrated increased speciation with sexual selection, the highest rates of speciation were seen in Skates (Rajiformes) and Neotropical Freshwater Rays (Potamotrygonidae) which highlight the colonization of novel habitats.

VDCH predicts an increase in speciation with live-bearing as this provides an arena for genomic conflict between parents possibly increased sexual selection. While diversification rate increases with live bearing and matrotrophy this is due primarily to different extinction rates

Understanding repro mode evolution in sharks and rays we can test different theories about how these traits relate to diversification dynamics (i.e. rates of speciation and extinction): the Viviparity Driven Conflict Hypothesis and the Novel Ecological Opportunity hypothesis.

Live-bearing and matrotrophy co-evolved with increasing body size, shallower depth, and more tropical distributions. Larger maternal body size accommodates retained embryos, and increased foraging efficiency with reduced predation risk may allow for more maternal investment

Egg-laying is ancestral and live-bearing and matrotrophy (additional maternal nourishment beyond the initial yolk) have evolved multiple times. While some groups are invariant (all skates lay eggs), groups like the requiem sharks exhibit diverse reproductive modes and habitats

The sequence and drivers of the evolution of live-bearing and matrotrophy are fundamental questions in vertebrate macroecology, and sharks and rays with their reproductive diversity (everything from egg-laying to placentas) are an ideal group for addressing these questions.

Hot off the press! Out now in Current Biology 'Maternal investment evolves with larger body size
and higher diversification rate in sharks and rays'

Read here:
authors.elsevier.com/a/1jCxB3QW8S6E…

Massive thanks to my co-authors Matt Pennell Kara Yopak and Nicholas Dulvy